When we season metal with oil , basically we heat the oil till the hydrocarbons break down leaving behind a largely carbon film. Carbon likes to form complex structures, ( think Tim a carbon based life form)
The residual leaves behind a thin polymerized film that protects the metal from rust & is realitively non stick.
Different people suggest different oils , from very low smoke points (flaxseed) to high smoke point ( peanut) & everything in between!
They all work!
In theory a low smoke point may be easier but practically it doesn't matter.
Just use the vegtable oil you have around the house.
Or do what grandma did, just cook on it, frying bacon , burgers etc will creat a good seasoning