Thanks for writing to health care magic.
First a physical examination will rule out any physical conditions like anemia
which may cause difficulty in focusing on any thing. Some times haemoglobin
profile may be required. If every thing is normal your attitude towards your studies should change. You should set yourself goal to work on. Think of the importance of studies. Read some motivational books. Get some support from your teacher or psychologist
Continue to ask further queries as required.
Hope this helps.