For those who are on windows and were struggling to find an working answer here's mine: pynput.

Here is the pynput official "Monitoring the keyboard" source code example:

from pynput.keyboard import Key, Listener

def on_press(key):
    print('{0} pressed'.format(
        key))

def on_release(key):
    print('{0} release'.format(
        key))
    if key == Key.esc:
        # Stop listener
        return False

# Collect events until released
with Listener(
        on_press=on_press,
        on_release=on_release) as listener:
    listener.join()

The function above will print whichever key you are pressing plus start an action as you release the 'esc' key. The keyboard documentation is here for a more variated usage.

Markus von Broady highlighted a potential issue that is: This answer doesn't require you being in the current window to this script be activated, a solution to windows would be:

from win32gui import GetWindowText, GetForegroundWindow
current_window = (GetWindowText(GetForegroundWindow()))
desired_window_name = "Stopwatch" #Whatever the name of your window should be

#Infinite loops are dangerous.
while True: #Don't rely on this line of code too much and make sure to adapt this to your project.
    if current_window == desired_window_name:

        with Listener(
            on_press=on_press,
            on_release=on_release) as listener:
            listener.join()

it can be done using the msvcrt module as the following:

import msvcrt

while True:
    if msvcrt.kbhit():
        key = msvcrt.getch()
        break

or the keyboard, although i am not sure of how of a good practice this code is:

import keyboard

while True:
    try:
        print(keyboard.read_key())
        break
    except:
        pass

if this is bad practice please informe me in the coments so i can mark it as unfavored

thankyou.

Use Tkinter there are a ton of tutorials online for this. basically, you can create events. Here is a link to a great site! This makes it easy to capture clicks. Also, if you are trying to make a game, Tkinter also has a GUI. Although, I wouldn't recommend Python for games at all, it could be a fun experiment. Good Luck!