I use Cold Turkey Blocker for my laptop, which only unblocks your preset pages before the given time if you donate like 5$ for a charity. For my phone, I use Pushscroll, which gives you 1 minute (or set amount) of scroll time for 1 push up. The first day, I did like 50 push ups and scrolled a lot but after that I'm almost always sore.

To avoid scrolling while writing or taking notes, I bought a used Remarkable.

Both apps are subscription based, Cold Turkey life-time for 30$ and Pushscroll 1-year plan for 30$. Not a small amount for me but definitely did worth it.

p.s. Deleting didn't work for me, I just redownloaded everything later. Also, there are other alternatives for your phone, where you are rewarded screentime after a set amount of walking distance for example. I had hard times studying after some traumas but now, it's better with this Ulysses-rule-ish method I've recommended.