PROBLEM I can’t make it so that pressing a button releases a cartridge that can destroy an enemy
What have you tried so far ? Post a screenshot of your blocks
I don't no how do it
A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook App Inventor 2 Book: Create Your Own Android Apps ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
There is a free programming course here Course In A Box and the aia files for the projects in the book are here: App Inventor 2 Book: Create Your Own Android Apps
How to do a lot of basic things with App Inventor are described here: How do you...? .
Also do the tutorials Our Tutorials! to learn the basics of App Inventor, then try something and follow the Top 5 Tips: How to learn App Inventor
Taifun
Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.
Have you tried this tutorial?
It shows one way to shoot something.
https://appinventor.mit.edu/explore/ai2/space-invaders
also these topics might be helpful to design your app:
Community discussions about shooting something