I have had bad teeth since 12 4 years ago i lost the gums on my front two teeth my dentist said he cant fix it. will i loose them?

Perio: You are quite young to have such problems. Can't diagnose specific problems over internet. Although you can't change the past, you can strive to do the best for the future. I recommend you get a consultation with the best General Dentist & the best Periodontist in your area. Get recommendations. Then discuss both how to restore health to you mouth & what you need to do to prevent future problems.

Perhaps: Ask your Dentist to refer you to a qualified gum/bone specialist, a Periodontist, for an evaluation.