Lost IPad Charger

Trying to find a new iPad charger seems difficult couldn’t find one in the Apple store so looked on eBay they only have second hand ones and I’m confused now cause I bought one that said 10w and then as I wasn’t sure I bought another that says 12w is it possible to use both or is one better than the other or do they belong to different iPads I think I’m looking for 7th Generation or earlier