We are happy to have you join us :D
Feel free to go ahead and start looking for partners are creating roleplays. (I don't know if that's what you meant by create your own world here.) If you have any questions don't hesitate to ask. :D
we have tons of RP world building exercises you might like, and using your own world in your own RP's is a wonderful idea, as long as your partners understand and are on board with it :)