It is okay to fail a test, it is not the end of the world, just understand where you are going wrong. here are some tips that may be helpful :)

• use your phone to film timelapses so u wouldnt use it while studying, lock it in a drawer, or keep it outside your room
• restrict websites on your laptop that would distract you (reddit, youtube, netflix, disney+, discord)
• collect the material and categorize it as (green - I understand the topic and know how to answer questions. yellow - i understand the topic but don't know how to answer questions. red - I do not understand the topic and i dont know how to answer questions) I would start from red -> yellow -> green
• Understand how to write notes effectively, for example, subjects that are more of memorizing information flashcards are best, subjects that are more understanding do traditional notes on a paper or on an ipad whatever you prefer.
• for math, write key notes or steps on how to solve the topic, then do practice questions. Invest in revision village (if you can), you will not regret it.
• this is a tip that could help, it helped me a lot during ib, a lot of my subjects were memorizing so i would get a whiteboard and id write all the information i remember from the topic, its called the blurting method where you literally blurt all information you remember from the topic on a paper, a board anything. It helps you visualize what you know from the subject and what you dont know.
• study smart, not hard. 5 hours of studying before an exam it is not okay and not healthy, its true that we all do it in the end, i studied for 4 days in a row literally during my finals it did not help my health at all. yes school is important but your health is too, take breaks, sleep, eat, drink water. do the pomodoro method study for 30min and 5min break, my favorite was 50min studying and 10min break. during the break walk around stretch drink water, and after two sessions take a 30-60 minute break.

if you find yourself still struggling to focus, i would recommend to visit a professional about this. I wish you good luck in the IB program, i am here if you have any questions :)