Hello there, Vel!
Iwaku is a fantastic place to unleash some of that pent-up creativity and share with creative, fun people (we have lots of those!).
I'm Kitti, by the way, good to meet you.
I have some links to give you a helpful little mini tour (yay for showing you around, sort of).
This is where you can sign up for the roleplays found in Modern, Scifi, Fantasy, and sometimes Mature. Generally, they will have you post a character sheet in their thread, a new sheet for each roleplay! You can also start signups for a roleplay of your own here.
This is where you can find jump in games, which typically have no sign up thread. You just start posting!
These are super important for rolplays, but there are LOTS of nifty things here that I didn't even touch on, so you should also take a look around to and discover more about us.
If you need any help, please do ask!