Characters are usually evaluated/approved by the GM of the plot(s) you want to join, or the faction manager for the faction the character is for, but any "vet" player can provide advice. The chat may be a good place to find help. I'm willing to look at your WIP character, too! Chances are you're not going to have issues with making a character, unless they're something related to some technical detail of the setting (like, saying your character enlisted in the Star Army before the Star Army was created)...which is usually something only old characters run into, and then we can just adjust things to fit. The main thing is just thinking of the character's essence, like personality, and finding an RP.
PS: Also, you can always make a "disposable" first character to test the waters before making a detailed one.