I am 15 as I said in the title and I actually have pretty bad hair loss in the left corner of my head. A big chunk of hair is missing but on the right side there is almost no hair loss. Will the hair loss stop with taking puberty blockers? Will they even regrow? Or regrow with estrogen injections? https://imgur.com/s5i9HRX

It could be signs of any number of medical conditions. One I have had experience with is a thyroid dysfunction - which can cause significant hair loss. Best bet is to go see your GP and start the conversation there. Its likely he'll run some bloodtests and/or refer you to a specialist.

I am not a doctor and don't know what the cause of the hair loss it but a doctor should be able to tell you. It looks something like male pattern baldness and if that's the case, there are medications that can stop the loss and allow regrowth if the hair loss is recent. Blockers will also do the same thing as both types of medications control or affect DHT. It's important that this be addressed as soon as possible for maximum regrowth as hair that have been gone for a long time will not regrow.

I third the recommendation of seeing a doctor.  As far as I know, typical male pattern baldness is relatively symmetric.  Asymmetric hair loss seems suspicious.  Regardless, if you want to stop it, you'll need to see a doctor either way to get a prescription or a diagnosis.