By the description you have provided it appears that you are suffering from androgenic alopecia
or the common male pattern baldness
. It may be inherited from either side of the family and usually starts in young adulthood.
Currently, two medicines are approved by FDA for prevention of hair loss. These are Minoxidil
. Both medicines prevent thinning of hair and may help in regrowth to a limited extent. The effect of therapy is usually visible after 3-4 months and lasts as long the medicines are consumed. Telling you the brand names would be unethical on my part so I would refrain from that.