If you overfilled the oil then you can drain some out. There are small hand held pumps that would work fine for the purpose. The exact process would depend on what you overfilled and how much. If the overfill is slight it might not matter on some things and be a big problem in some other. You did not say what you overfilled to give a real exact answer.

overfilled engine oil

What are you talking about, they were overfilled.

jammed, overfilled, congested, crowded

You have overfilled the washing machiene.