How To Improve Penile Size?

hello doctor,i am a 20 years old boy,my penis is of 6.29''(erected) in length and 2.4cms in width(width of the head of it),and my penis head is thicker then it comes thin at end structure...

i do masterbate 3-4times daily...

1.is it wrong to do so many times at a day?

2.how can i grow my penis both from length and width?

3.is there any risk of loosing longibity for so many times masterbation now?

4.and how can i be longer in bed?



plz send me some suggesstions...