I know how to code, but I'm new and can't find where to insert the coding :c. Where do you add all that stuff?

For Subeta?

Custom CSS (for custom site layout): Personal -- User Dashboard -- Custom CSS (http://subeta.net/preferences.php?act=customcss)

User Profile: Personal -- User Dashboard -- Profile (http://subeta.net/preferences.php?act=profile)

Pet Profile: Personal -- Pets -- click the Edit icon for the pet -- Edit Description

Moving to Help & Questions!