You can try one of the gang or one of their friends like Guido, if you know their personality well. Or one idea, to give rp a try is to pick a character you like, but maybe don't feel you can rp them well, and make an oc who is their sibbling. For example being one of Petrie's or Ducky's sibblings.
You can also pick a dino type that you like, longneck like Littlefoot, threehorn like Cera, or another type of dinosaur, like a maiasaur, clubtail, Iguanadon, or another dino type that you like and make an original character that has mainly your personality.