So many other students I know are struggling too. It's harder with mental illness on top of everything, but university is objectively difficult work for anyone... generally too much course content is crammed into short timeframes, lots of deadlines, etc. You're not abnormal for finding this all overwhelming. I guess there are some students who are able to coast through, but I'm sure some of those apparently not struggling are incredibly stressed out as well.

Does your uni have counselling services? If so, make sure you're seeing one. For the sake of it, but also because they're familiar with your uni experiences and they can provide paperwork should you experience something mental-health-wise that disrupts your study or causes you to miss an assignment etc.
In addition to seeing a psychologist at uni I'm also signed up to the disability support services -- it allows me some accomodations like small exam rooms, time extensions, access to quiet study rooms in the library, and a person who helps me organise myself and keep track of assignments. So look into that too.

Another thing you can enquire about are any study help programs and workshops. There may be services where you can get tips on how to study effectively, time management skills, how to take notes, etc. If not, google that stuff. Learning some of those skills helps.

Hang in there It is tough so good on you for sticking it out.