Welcome! :>
You'll get the hang of it pretty quickly. Role playing is writing at a partner or group in turns, you usually only using a character or two to interact with theirs. In one on one requests, people generally want romance/chemistry as an option regardless of how romance-focused the RP is, so they outline whether they want a male-female, male-male, or female-female couple as the focus (MxF, MxM, FxF respectively).
Then here on RPG we have different levels of writing. Free is loose and allows for single sentences or one liners. Casual writers usually wants at least a paragraph or two to respond to. And Advanced players want multiple paragraphs and generally higher level, complex stories. I'd recommend starting at a low casual-casual level for ya first RP or two.
I prefer group RPs, but one on ones are definitely an option, and they're split into different threads for ya convenience.
I hope that helps explain some of the basics ya asked about. Feel free to ask anything else and again, welcome to the guild! I think there are information dumps about the site, too, for new RPrs