Your primary typing is the first typing listed, your Skeledirge, for example, has a primary type of Fire.
Pokemon do not have 2 primary typing, Skeledirge's Ghost-typing is a secondary type.
I see what your saying, but it still doesn’t make sense.
I use Skele for his Fire Attacks and his Terra Fire increases the damage.
It should show his Fire Tera on Pokepaste, but it doesn’t.