I need Microsoft office full version for iPad 8th gen

See the following from https://apps.apple.com/us/app/microsoft-word/id586447913

To create or edit documents, sign in with a free Microsoft account on devices with a screen size smaller than 10.1 inches.

Unlock the full Microsoft Office experience with a qualifying Microsoft 365 subscription for your phone, tablet, PC, and Mac.

The iPad 8th generation has a 10.2 inch screen. You will need to subscribe to Microsoft 365 (if you haven't already). You can download the individual Office apps (Word, Excel, etc) from the App Store on your iPad. You can subscribe to Microsoft 365 through an in-app subscription through Apple or you can subscribe directly with Microsoft via the "Buy Now" button at the bottom of https://www.microsoft.com/en-us/microsoft-365/mobile/microsoft-365-mobile-apps-for-ios