Help,I want to create a forum from 0

If you have your own VPS already and intend to support it yourself I highly recommend you install Discourse yourself using the official guide discourse/docs/INSTALL.md at main · discourse/discourse · GitHub

You may surprise yourself!

It’s OK to make mistakes and you will learn a lot. If you get stuck, you can ask here, or search. Many many have trodden the same road before.