Hi there, did you create your Master Account? If you have created your Master Account and it has been accepted, go here https://redcountyrp.com/dashboard and click on the blue button to create a character.
Okay, so you created your character, thats good. Now, use your Master Account name and log it with it, not your character name. About the skins, you need to purchase them in the clothing store and then you will be allowed to change your skin in the UCP.