If you are using the CLI, (command line interface), that is, the text terminal in Ubuntu Linux, be sure you are actually running Python interpreter within your CLI.

From the command prompt $, type "python" or perhaps "python3". That should get you a python prompt that looks like this: >>>. That will be where you enter your commands into the python interpreter.

From the python prompt >>> you can type your simple commands.

If you are saving these to a program/script as a .py file, then to run the script you would need to type "python ./hello.py", in order to recruit the python interpreter to run the script.

If you are using a specific development environment (IDE), like VS Code, Eclipe, or PyCharm, or some other, let us know. These are special programs for writing code where you type and save your file in a window within the program. These have their own processes for running the program from the IDE. Most will have a play button somewhere to run the script and give output in a separate pane, e.g., near the bottom of the window as in VS Code.

Your program does not output anything because you are never calling your function.

This will do what you expect:

def GetNum():
    x = int(input("Input something: "))
    while (x > 0):
        x = int(input("Input something: "))

    print(x)

GetNum()

I removed the function argument Text, added a call to the GetNum function and added type conversions from str to int for both input() calls.

Using the Python Extension Run/Debug commands

Notes

1. I recommend reviewing the official Visual Studio Code Python documentation and tutorial. That provides several of the basics, with running and debugging the "official" way.

2. There are multiple ways to configure built-in launches:

   • When running or debugging Python in VS Code, there are a few options that you can change in your "launch.json" file. See this answer for more details.

Run or Debug with the built-in Python extension commands

You can run or debug using the "triangle" icon and dropdown in the upper right of your editor window, when the editor window is focused on a python script file (i.e. typically a file named *.py).

You may need to setup a run/debug configuration to use this (see below), or it may automatically step you through creating one.

The output will normally go to a new "Python" terminal in the "terminal" window (Ctrl-`, to open it). See this answer for how to change that behavior.

Setting up a run/debug configuration

Easy option:

• Use the menu item **Run/Add Configuration, and follow the prompts at the top of the VS Code window.
• Some of the additional details are shown below.

More involved option:

• Click the run/debug icon on the left vertical icon toolbar.
  • 
• The window says "RUN AND DEBUG" at the top, with a drop-down that shows "No Configurations" for a given folder or workspace until you set this up.
• The gear to the right of the dropdown will have a red dot if you need to configure this:

Updated Image (1/2022) - Changed from just 'Debug' to 'Run and Debug':

• Click the gear icon (or in the menu, use Run/Open Configurations), and in the middle at the top, Visual Studio Code will open a window titled "Select a debug configuration".
  • The available options will depend on exactly how you have Visual Studio Code setup and configured
  • There should at least be a "Python File" option with the Python extension installed. Select it.

Now your debug configuration box on the top left of the debug pane should say "Python: Current File":

Visual Studio Code will add a file to your current workspace or working folder called .vscode/launch.json, and opened it for edit.

By the way, U said after you run "pip --version" nothing was displayed, I think this means you didn't install python correctly, pip should be installed automatically after you install Python. Just remind, make sure set the right Python path to your computer system path, set the "path" variable to the correct python istalled path.
In my opinion, you should uninstall python, and reinstall again.Any problem please let me know.

Try running the following in the Ipython console.

%config InteractiveShell.ast_node_interactivity='last_expr'

This is the setting description:

ZMQInteractiveShell.ast_node_interactivity=<Enum>

Current: 'last_expr'
Choices: ['all', 'last', 'last_expr', 'none', 'last_expr_or_assign']

'all', 'last', 'last_expr' or 'none', 'last_expr_or_assign' specifying which 
nodes should be run interactively (displaying output from expressions).