Is it logically possible to prove that something does not exist?

I’m not entirely sure I know what I’m talking about here but… Surely it is possible to prove that something does exist but not possible to prove that it does not? Because that would require knowing everything about everything would it not? Of course hypothetically if you did know everything and everything then it would be possible to prove that something does not exist… but…

it isn’t humanly possible to know everything is it?
Does that make sense?