Oil in park plugs, valve cover or gasket

What is your question?

Dang after i final got to the spark plugs and all, i found oil in 3 plugs, is this a valve cover gasket or o-rings. Just on the side note, i was adding oil to the car couple months back and it spilled under the engine cover a good amount ,could this got into the plugs somehow, because their were small pools of oil after i took the engine cover off, around the coils