Welcome to Wattpad!!!!
I've heard from multiple sources you don't need warnings, so I'll hold off on that, though if you know anyone with innocence that is joining, you are going to want to warn them.
You can write, read, or both! I mostly read an excessive amount of fanfiction, but there's original stories on here, too. Eventually I'll be publishing some original stories myself (as I can't write fanfiction very well but I might someday) but that's going to take a while as I keep rewriting everything and changing the plot seven hundred times. It's normal.
I strongly prefer this community to AO3 or fanfiction.net, so once you start you'll probably become addicted. So yeah! That was long and annoying, but basically, welcome to Wattpad!