So I'm making a game and for the life of me, I can't figure out how to implement collision. It's a game inspired by counter-strike (and will eventually actually BE more like it later on) with a top-down view of a person with a gun, and when you press left or right, the player will rotate, and when you press forward or back, the world moves away, making it seem that the player is moving. I made it so that a tilemap will draw relative to the x,y of the player as well. Now all I need is collision with the walls. Every way I go about it doesn't work. So I need help, or some sort of tip or something. I'll include a file with the source code and game if you want to see it. Thanks!

So I want to make a game in grayscale. I found a tutorial for it: https://www.omnimaga.org/axe-language/axe-greyscale-tutorial/, but when I tried it, it came out as black, light gray with dots in it, and white. I think dark gray came out as light gray (as mentioned before), and light gray came out as black. Could someone please tell me what I'm doing wrong?