Have you measured yourself using the r/abrathatfits guide? A true 36B is pretty rare. More likely you are a 32D at least. That's 2 cup sizes there, though probably 3. Next, go on birth control for a few months are you will get another cup to take you to about 32F. As for the remaining cups, you can either get implants (probably need about 800cc) or you can wait until you gradually increase with age or more rapidly with pregnancy.