Welcome, Abigail! Wonderful to see new people coming in.
These are no official rules, but there are people who enforce their own rules. Some of the most common things: don't plagiarize, don't post illegal contest, and many of our older users suggest that you create posts a maximum of 1 time per day (Threads like this can be unlimited, however).
Anyway, these aren't too restrictive, so you can definitely have your share of fun here. Cheers!
Thank you very much for this great advice