How can I say if someone doesn’t help and do the opposite of helping?

Question

Answer

There are various different ways of expressing this idea (and it completely depends on the context) but one option might be "You're not helping, you're only making things worse".

Answer

A common antonym of to help is to hinder. It depends on how they are 'not helping', though.

The energy drink actually hindered his ability to concentrate.

His comments were more of a hinderance than a help.

Answer

Hello.
You can say that person is exacerbating things.
Or you can use an idiom.
"Digging yourself into a hole" -> That person is digging themselves into a a hole.