Can I use Atom for unity game development with c#?

I don’t like VS code as it keeps up messing things up. ATOM being simple can we use it for unity and c# game development?

I think you will need rather more than Atom for game development.

Based on your interest in Unity my suggestion is install HaXe and then write HaXe code in Atom.

Here is just one tutorial I dug out for you.

I will comment that VSCode has better extensions for using HaXe but there is no reason why you cannot use Atom as your HaXe development platform. I suggest that you create custom HaXe build and run commands in Atom process-palette package. These can be bound to toolbar menu items.