A perfect platform for young writers is WattPad, an international writer's and reader's site. Bascially, you can post ANYTHING-- a script, story, novel, poem, novella, ext. and get readers, votes, and comments about your work. And if you don't feel really like doing that, you can aleways read other people's work and comment on that.
If you write on WattPad, you can choose form many different copyrights. There is All Rights Reserved, and a bunch of others that I don't know what they are or what the names are. It's very handy because you can also see the gender, counry, and ammount that each person read on you novel.
There have been many succssess sotries on WattPad, wherre books get milions of pageviews ab=nd then someone like Harper Collins (largest published in the world) buys the book and publishes it.
My username on WattPad, if you want to follow my novels and novellas, is Brooke_Writer. I am currently posting a warrior cats fanfiction on my page, but one other novella is on there- Kat and the Great Zoo After Dark Adventure.
I hope you join, and be sure to let me know your username in the comments below. I would love to follow you!