Moped Army

I was wondering if this would work good on my moped. I think it should, but just making sure. I also dont understand how to actually "fill" the transmission through the little hole with a bottle like this. On my transmission, there are like 3 holes. I think the one on the very very bottom is the drain, one on the top is fill, and there is a mid one I think, not sure.

http://www.amsoil.com/storefront/atf.aspx