Is there any way to speed up breast growth?

Okay so literally no, you can't really speed up breast growth. Your body does its own thing when it's ready, and everyone's timeline is different.

Breasts grow because of hormones, mostly estrogen, that start doing their thing during puberty. It's not something you can control with what you eat, or any special exercises, or like, magic potions. Some girls get theirs super early, some later, and some just stay smaller. It's all totally normal, and whatever size your breasts end up being is the perfect size for you.

Also, your breasts will keep changing for a while, like through your teens and sometimes even into your early twenties. They might get a little bigger or change shape, and that's just part of your body growing up. So just let your body do its thing!