Hi.. Hairfall have many reasons. Like nutritional , hormonal example PCOD , stress induced ( Telogen effluvium ) , skin diseases ( alopecia areata ) etc.. etc...
Always finding a cause behind your hairloss is first step . Then comes the solution or treatment
There are many medicine available for hair regrowth, shampoos, hair supplements and you also have therapies like PRP therapy, Mesotherapy , stem cell therapy, laser hair therapy.. and finally hair transplant is also available. There are mutiple options to get back your hair.
Consult the right doctor, don't go for instant solutions. Like solutions provided by TV advertisements.
Hope this helps