As for the things that will happen to you with puberty, these can be upsetting.
But remember, many Susans' members have only managed to start when they are well into being fully grown and just look. They are beautiful.
OK, It's a lottery to an extent. It would be great if you could start now. But you can't. You know that.
You can begin when the opportunity arises.
One thing I've learn here, is it is never too late.
Now, think very carefully about your plans. Don't, whatever you do, throw away your opportunities for education. That must come first, before anything.
Don't lose hope.