I have massive boobs D-cup for my age what do I do,

Best thing for you would be to get a good supportive bra.

I do thanks,

Good for you! Glad you have a good bra. If you are asking about anything else, such as reduction surgery, doctors won't do that until you have completely developed. That is usually around the age of 21.

Am I to young to have D-cup boobs, I know I am to young to have boob reduction