How can one get motivated to study?

Hello doctor,

I am 20 years old male. There is not a single day when I sleep happily. And the reason is that I am not able to study. It is not that the syllabus is too tough for me. It is just that I do not sit too long and for that matter, I do not sit to study at all. I know the consequences. This semester is important for me. If I perform badly in this, my parents will kick me and throw me out of the house. I need to study well to get a good branch. Just the thought of not studying is making me lose my life. I am feeling completely frustrated and am with no hope. I also get suicidal thoughts. So, I thought of consulting someone. If I start studying, I will do miracles. But, I get deviated easily. I feel like I love buying troubles by not studying. Please guide me on how to be motivated to study regularly. Just one act of not studying is making me lose my happiness. And, I often get headaches too due to irregular sleeping habits, may be. Please help me.