How do you turn your One Plus into a dumb phone ?

I am a student and I find my smartphone very distracting and as result, I procrastinate and lose attention. I am reluctant to buy a dumb phone because all my downloaded courses are on the phone. Also, Uber. I tried deleting social media and useless apps but I still find myself hooked by the gratifying nature of the internet. Any tips to make your OnePlus into a dumb phone ?