PICO-8, the incredible 8-bit virtual console, is now available for free, for education purpose.
If you want to start making games, it's the goat: https://www.pico-8-edu.com/

I made ❤ Knytt and ❤ Destruction Carnival with it.

• Type INSTALL_DEMOS to install all the demo files for learning how it works
• Then type CD DEMOS to move to the demos folder you have just created
• Type LS to see all the demos files in that folder
• Load a demo using LOAD JELPI (or any other demo)
• Run the demo you just loaded by typing RUN

Now you can press Escape key twice to enter the Editor and mess with the code, sprites, map, sound and music.

Pico-8 is easily one of the most used software for making little games, so you'll find all the explanations you need on the Internet, like those two:

• https://pico-8.github.io/awesome-PICO-8/
• https://www.lexaloffle.com/pico-8.php?page=resources

Or this really well-made interactive tutorial: https://demoman.net/

For example, you could start doing this: how to make a Space Shooter tutorial