Not GP here, but I've gone through a similar brain reset exercise recently. There's no good way to do it, because it's essentially just dopamine deprivation. Caffeine withdrawal, internet withdrawal, gaming withdrawal - whatever stimulus you're using, you take it away and suffer for a while.
Quitting my corporate gig has also been massively helpful - our big tech overlords were committing Guantanamo level atrocities on our minds via Slack overload, and I will never return to that kind of environment. I'm barely exaggerating.
If you're a podcast kind of learner, Huberman has an episode on this "dopamine fasting" concept.
Read a bit in bed before sleeping, make this a daily habit; leave all electronic devices outside of your bedroom. No screens in bed; let your mind learn to accept that.
Start with books you can focus on now, gradually move on to more complex works. Don't feel bad about picking a genre which really draws you in. You don't have to read Dickens on day one (although he is a great writer, older works ask a lot in terms of focus and frame of reference, including some understanding of society back then and there), and it's fine to indulge in Young Adult fiction if that works for you (Harry Potter not too demanding to read, and pretty good too).
