You can install applications different ways. Terminal, the Ubuntu Software Center, and Synaptic.

With the Ubuntu Software Center, you just open it from the Launcher, and search for the application that you want.

If you know the right commands to install via terminal, then you'd just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, you can run the command(s) needed to install the application.

For synaptic, it has to be installed on you system. To install it, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt install synaptic

Once installed, you can open it, and search for the application that you want to install, and just mark it for installation.

Also in some cases, you have to download either a .deb file in case of your question about Chrome, and have to manually install it, or a .tar.gz file, and that also have to done manually.

Now as far as Chrome is concerned, you can install it by downloading the .deb file, or just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

For 32bit

wget https://dl.google.com/linux/direct/google-chrome-stable_current_i386.deb
sudo dpkg -i google-chrome-stable_current_i386.deb

For 64bit

wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
sudo dpkg -i google-chrome-stable_current_amd64.deb

If you encounter any error during the installation, when its done do

sudo apt -f install

For pros and cons of the different ways to install see this Post.

^{Source for Chrome installation: Google}

Addition

Installing software in Ubuntu can be done several ways:

Ubuntu Software Center

You can search for an application, or go through the categories:

Synaptic Package Manager

You can search for an application, or go through the categories:

Installing via Terminal

Installing from terminal can be done in several ways:

APT
You can search for an application. The command to search for software is:

apt search <application_name>

Adding Repositories:

Edit the sources list file, and add

sudo -H gedit /etc/apt/sources.list

Or add from terminal

sudo add-apt-repository <repository_name>
sudo apt update
sudo apt install <application_name>

Others ways you can install

Manual download of a .deb (Debian package):

• Once downloaded, you can double-click on the package to have it open in the Software Center, from where you can install it.

• Or, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, navigate to the download location, and run the command(s) below:

  sudo dpkg -i <package_name>.deb
  

Other options:

• .rpm files are packaged for Fedora or Mandriva, but you can use alien (you can install using Synaptic) that allows you to convert .rpm files to .deb. (may not work all the time)

• .tar.gz files are compressed. If you see the .tar.gz, it could be compressed files that have a pre-compiled binary file, or files that have the source code allowing you to compile the application from source. To find out how to install from a .tar.gz, see How to install from a .tar.gz.

For more info see Installing Software, or A beginners guide to installing programs in Ubuntu

Use dpkg - package manager for Debian.

dpkg -i yourpackage.deb to install a package.

In the terminal I chose directory and did: "sudo apt-get intall *.deb"

Here there are two problems:

1. intall is misspelled, it should be install
2. apt-get will install local packages if a path is provided in the way of ./package.deb or /path/to/package.deb

This should achieve the desired result

sudo apt-get install ./*.deb

This will install the packages and any dependency needed if it can find them.

Is there a command in Ubuntu, given a command name, it will return that information?

No, there isn' t. You need to do some investigations. First, the type command will reveal information about the nature of the command:

type <command>

This command will indicate whether it is a shell built-in, an alias, and if an executable, whether it is hashed, i.e. indexed for speedy retrieval –this indicates you have run the command at least once before in the session–, or where the binary is located.

The place where the executable is installed already hints towards how a package was installed. The command which reveals its location:

which <command>

• Executables of packages installed using the regular APT system, i.e., from the Ubuntu software repositories, from a PPA you added or from a downloaded .deb installation file, will typically be installed in /usr/bin or /bin. Use the command dpkg -S filename-search-pattern to find out which package has installed the file (source).
• Executables installed by Snap are exposed in a dedicated directory that is added to the PATH, i.e. /snap/bin. Confirm that this is a snap package by finding it in the output of snap list.
• No executable are exposed in the PATH by Flatpak. You can, however, tell whether a package is installed that way from the output of flatpak list --app.
• Executable AppImages can be placed anywhere. There is thus no general method to recognized their source. Typically, however, they will not have been renamed and then can be easily recognized by their extension .AppImage.

In case your package was installed as a .deb, you can further differentiate looking at the output of:

apt policy <package>

An URL in the output will directly hint from which source the package came if it was installed from a software source. The absence of an URL indicates the package was installed from a locally downloaded .deb.

install not only copies files but also changes its ownership and permissions and optionally removes debugging symbols from executables. It combines cp with chown, chmod and strip. It's a convenient higher-level tool to that accomplishes a common sequence of elementary tasks.

An advantage of install over cp for installing executables is that if the target already exists, it removes the target file and creates a new one. This gets rid of any current properties such as access control lists and capabilities, which can be seen both as an upside and as a downside. When updating executables, if there are running instances of this executable, they keep running unaffected. In contrast, cp updates the file in place if there is one. On most Unix variants, this fails with the error EBUSY¹ if the target is a running executable; on some it can cause the target to crash because it loads code sections dynamically and modifying the file causes nonsensical code to be loaded.

install is a BSD command (added in 4.2BSD, i.e. in the early 1980s). It has not been adopted by POSIX.

¹ “Text file busy”. In this context, “text file” means “binary executable file”, for obscure historical reasons.

Ubuntu does have Minimal CDs that are 35MB - 40MB in size that install the base system and allow you to do command line installation. They also let you choose only the packages that you want to install.

https://help.ubuntu.com/community/Installation/MinimalCD

Generally when you install a program, you will be able to run it from the command line by typing the name of the program installed. Note that this name will not always match the name of the package (e.g. alsa-tools provides as10k1, hda-verb, sbiload and us428control).

As discussed in the comments by George and Terrance, the program must also be in your PATH variable so that you don't require the full path to run it. For some reason "cowsay" is not, so you can temporarily add it as described by Terrance using:

PATH=$PATH:/usr/games

If this works, you can permanently add this location to your path variable. This can be done by modifying .profile, .pam_environment, or other locations as described in the references below. For example, adding the following to ~/.profile should work:

export PATH="$PATH:/usr/games"

The above will take effect on the next login.

References:

• How to add a directory to the PATH?
• https://help.ubuntu.com/community/EnvironmentVariables#Persistent_environment_variables