Water bath vs pressure canning

Hi! I'm pretty new to canning and there is so much info out there that i'm just getting confused.

Previously I have only canned syrups, jams and vegetable broth. But I have only used the water bath method. I understand from some reading that some things have to be pressure canned and I can't just "substitute" it with the water bath method, is that information correct?

I was going to make a mushroomsoup (no dairy) and can it via water bath, but am seeing some recipes say that it can only be pressure canned, can I do this or will it not be safe?

Thank you in advance!!