how to update ios10 for ipad 2

If you have an iPad2, iPad3 or original iPad mini, these devices cannot be updated beyond iOS 9.3.5 (WiFi Only models) or iOS 9.3.6 (WiFi & Cellular).

Apple formally ended update support for these devices in September 2016. None of these models can be updated to iOS 10 or later versions, as the internal hardware does not meet the minimum technical requirements for new versions of iOS/iPadOS.

Many App Developers have also dropped support for older devices and iOS versions preceding iOS11/12 - and have withdrawn older versions of their Apps from the Apple App Store.

If Apps that you need to use now have higher minimum iOS-version requirements, your only option is to replace your iPad with newer model. Even the basic current iPad7 model supports iPadOS 13.x - and has hardware specifications that will vastly outperform your old iPad

I hope this information is helpful - if only in clearly stating your current options.

Not possible your iPad 2 is too old no higher than 9.3.5?