I'm sorry you're going through this. Obviously I don't know exactly how you feel because we aren't the same person but I've felt something verrrry similar. I'm not going to sit here and pretend I have all the answers but I will say this. I learned I am able to get things done if I put them into small chunks. Don't think about the big picture. I also find that I am more productive when around others. If you don't feel comfortable going to a library or something (I don't when feeling depressed) there are plenty of youtube videos or streamers who just study in their videos. It's designed for those with depression, anxiety, and/or adhd. As for the meds I can't give much advice as I am also finding my medication isn't working well enough. The last thing I want to say is that you've got my ear whether you want to talk or vent with no response.

I was your age when my first major depression hit. I can totally relate to everything you said. I thrived in high school. Absolutely thrived. Then, suddenly, third year of college came and I suddenly didn’t know how to put an outfit together. It’s so frustrating. Do you have any support?