Here is your code. S223C38E. I put the camera and solved some issues with the AI.
I changed a lot of things and left some commentaries on your code.
Important things:
-Always store your sprites on variables. Right now, the amount of sprites is low, but if you have to do this if you want to handle more enemies on screen.
-Use a speed variable instead of hard coding movement.
2そうだね プレイ済み