Welcome to Guild, [@DyingSpark] :sun

As for navigating, a lot of it is just exposure over time and getting used to the sections and what they're there for, since it's not a terribly difficult site to get through otherwise.

You shouldn't have a problem finding an RP since there are various genres going on, but also keep in mind that you'll need to practice patience here since some of the larger-scale RPs have a slower pace than others. 

In any case, explore and I'm sure you'll figure it all out soon enough.