You purchased a nearly 10-year old iPad.
Your iPad is too old for any upgrades/updates.
Sorry.
Apple ended support for 8-10 year old iPads, at least, well over 3 years, ago!
The internal hardware in that iPad is too old, too underpowered and completely incompatible with all later versions of iOS/iPadOS.
Virtually, all third party iOS app developers ended/stopped/abandoned supporting these old iPads over two years, ago!
There are virtually, NO MORE older iOS 9 or 10 compatible apps available from the Apple iOS App Store, any longer.
There are also, virtually, NO MORE popular or useful apps or games for these old iPads, any longer!
Especially multi-player games as game makers push for upgrade compatibility for best interactive user and cross device gameplay.
If you can, return this very old iPad model and get your money back.
If you need/want an iPad with an up to date iPadOS with access to current, updated apps, then you really need to seriously consider a new iPad model OR a much, MUCH “newer” and less expensive, used iPad models, from better known, trusted Apple product/device retailers/resellers, capable of running the latest iPadOS versions.
There are plenty of newer, older iPad models that can run the latest, current versions of iPadOS.
Sorry & Best of Luck to You!