Tidy up your workspace and clear it of distractions (to forcefully remove distractions on your phone, use the forest app)
Use an interval system (Pomodoro)
Trick yourself into doing the work (studying) for some reward (snacks, youtube, gaming, etc)
Listen to the right sounds/music
Figure out how you study; try different methods of studying and see what suits you the most and then stick with it
Understanding Concepts > Memorisation
Memorization with Strategies > No-Strategy Memorisation (i.e. if you have to memorize, do not do so blindly; use mnemonics, analogies, stories, grouping, memory palaces, whatever that helps)
Good luck