Some hair follicles can regrow as long as the hair follicles have not closed, disappeared, scarred or have not generated any new hair in years.
If your hair follicles are still intact and have not closed, disappeared or scarred then you can usually almost always regrow the hair follicles and regrow the hair.
You can use coconut oil to help promote your hair growth and do a hot oil treatment with coconut oil as I I've found using coconut oil and doing a hot oil treatment with coconut oil has helped to regrow my hair.
You can also wash your hair using Apple Cider Vinegar which is another great way of regrowing hair and helping to promote healthy hair and hair growth.
The Apple Cider Vinegar contains alpha-hydroxy acids that help to dissolve oil buildup on your scalp and in the pores, while the apple cider vinegar's acetic acid stimulates blood flow to follicles to encourage growth of your hair.