It's hard to say exactly when you know it will end. It's possible you will think it has ended and then some more hair will start growing in your thighs, or you get taller. I think at 15 it's unlikely it has ended for you yet but maybe? I think it's one of those things that once you turn 20 you will realize oh shoot, my body has stopped changing so much.

I also think that's hard to say. You CAN change until your mid 20s. Or be done by - random age. Depends on your genes and life style.
So at 15 you could be done or still have years to go. I'd say when you don't notice big changes anymore, you're probably done.

I wish puberty could be over now for me

im 14 im pretty sure my puberty has finished, like nothing has changed in months

im not sure theres much more that needs doing puberty wise lol think im pretty well done

I'm now 18 and I think my puberty finished when I was around 15-16. But as most people have said, it's really impossible to tell and it's likely that changes in our body or our mental development will continue into our 20s even if we don't notice them.

I hear U can keep growing until you are 21

When there are no more puberty-related changes. I guess for a girl, if you've not got any taller for a while, your hips have not widened any more, your breasts are not still growing and your cycle has become regular then I would say you're done.

You get a certificate of completion in the mail. You can frame it, or stick it on the fridge.