Okay, so let's pretend you're having a birthday party and your mom goes to the store to buy you some things for the party. She buys a cake, balloons, and some toys for you and your friends to play with.
The cake is a final good because it's something you can eat and enjoy right away. The balloons are also a final good because you blow them up and they're ready to use for the party.
But the toys your mom bought aren't quite final goods yet. They still need to be assembled and put together before you can play with them. So they're called intermediate goods because they need more work before they're ready for you to use.
Final goods are things that are ready to use or consume right away, while intermediate goods need more work before they can become final goods.