I'm editing a profile page and I'd like to edit {vb: raw block_data.fields}. I want to add some more things there but I have no idea where I can find it.
I'm not quite sure what you want to do, but that variable is a combination of all the fields. It looks like it's built up using the memberinfo_profilefield and memberinfo_profilefield_category templates. So if you want to change the formatting you might be able to edit those, but for other changes you probably need a plugin.