Don't worry too much if you can't do a lot at a time. I've never been able to revise for more than 4 1/2 hours a day, that is my total limit, and I still get good grades. When I get stuck and feel a bit tired honestly just getting up and going to the bathroom wakes me up a little. Anyway for studying I actually love putting on ambiance playlists on YouTube! You can get ones for specific environments, like cosy cafes or the Hogwarts common rooms, or videos that are meant to mimic a "study with me" video with clips of Rory Gilmore, BTS, etc. It sounds silly but I think these make studying much more fun
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I also think it can help to switch studying "activities", like go from flashcards to writing everything you remember on a page to drawing a mindmap or something like that! For me a study timer helps to motivate me as well, I use the app "FLIP" and you can see your studying progress per day, week and month
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Lastly I find it wayyy easier to study in the uni library than to study at home since there's less distractions and every else is there to study, so maybe try that too. Best of luck for your studies, you got this!!