very simple and very wide, it's hard to tell what's going on since everything is pretty small on the screen
the alien hitboxes are bigger than the aliens themselves so I found myself walking offscreen most of the time trying to avoid them
I see that this is your first game published to itch ever so 🎉 congratulations 🎉 !
(not to be rude but you might wanna research the topic of "Cameras And Viewports" in GameMaker's manual)
cheers