1997bumblebee – I have a classmate who worked part time, is planning her wedding and excelled our course despite language barriers because she ask a lot of questions in class and also have guidance from her friends in class.
Maybe you can try to find ways to get learning support from your classmates or lecturer. I find that 1-2 hours a week with them was more productive than struggling on my own. I also learn better if I ask questions after class when it is fresh in my memory. Eventually I can do most things myself.
For math, I would recommend having a standard formula list as reference and identify some patterns when you work it out part by part. I also refer to the examples in the textbook. If you have problems breaking down some parts, quickly ask in class or after class. Get a practice workbook for algebra and time yourself while doing it, I try to finish 15min before the set time. For bio and the other sciences,I think the key is to break down the information and digest it with the pictures. I watch YouTube videos on the topics if possible and draw mind maps. If you want, maybe I can show you how I digest information or suggest study methods for bio if you email some pages of something you’re struggling with and what ways are easier for you to learn to email@example.com.
My school advisor told me that health and personal issues like different learning method or problems concentrating are to be fixed myself but they can offer free learning support if I asked. There is no exception because people with adhd, autism and other disabilities passed the course.