Libraries are great for revision, music will help you focus but not if it has singing in it, so try instrumental-only music.
Put your phone on flight mode. hearing notifications is one of the biggest distractions for me.
Google the Pomodoro technique- this is really helpful if you have a short attention span.
Don't push yourself- setting yourself goals that you won't achieve will cause you to give up on the work.
Split your work time into small chunks separated by breaks to lower the load (Again, see Pomodoro technique)
Try to find a revision technique that works for you- for me it's mind maps, as i can clearly distinguish and track individual concepts and ideas. A good revision technique will help you enjoy revising more and so you won't be as distractible.
Doing practice papers for exams can be helpful as well as there's a set time to complete them, and there's more of a sense of satisfaction when you complete them. A major part of procrastination is wanting quick satisfaction.
If you find yourself becoming restless, take a 5 minute break, no longer, and have a drink and a snack.
Any questions or anything PM me or post here, I have ADHD so I've developed a few coping mechanisms that i find useful, and I'm happy to answer any queries