Hi welcome to health care magic....
You are very young aged boy...At this age it is normal to having masturbating habit ...
Masturbation is safe and pleasure giving habit ..
But according to my opinion try to avoid overhabit of that ...
You can masturbate two to three days in week..Avoid more than that to focus on study....
If you want to get rid of over habit of masturbation than daily
yoga will be helpful...
Pornographic videos and magazine watching should be less.
regular exercise done ...
Make short term and long term goals and fulfill it ...
Endulge in some useful activities and sports ...
Try to avoid remaining alone in room to avoid thought about masturbation.
It is better to focus on study rather than thinking more about this..
Hope your concern solved ..
If you still need guidence you can consult psychiatris session for more
counselling ....