do you have some tips for energy-concentration bust? Have a exam soon

White noise works for me and it turns of the overthinking distracted part of my head. Also sitting in a corner, although it sounds odd I find there is not much to zone out on.

Music with good tempo but not too interesting, caffeinated, break task into smallest part u can think to start with, a reward when completed that part, if your lucky your get into the flow and be done completely, if not reward, rest for a few minutes, repeat, worked for me, mostly

When I went back to school at 40, I struggled with concentration too! (I was finally diagnosed with ADHD and it explained EVERYTHING since my early childhood, LOL) You could try Lo-Fi music? I found the beats without lyrical distraction, helpful.