Failed in maths and chem exams in half yearly(12th PCM) and my physics exam is in few days..

I did whatever I could to score at least 40 in all three as I failed in them in last test too.. Is there anyone who can guide me what to do as I'm very confused as to what am I doing wrong . I feel like I completely destroyed myself. But I genuinely studied so hard but still same result, do t know what to do next. Help me!!!! 🙏🥲