How can I update my iPad?

Update in what way? Hardware? Software, if if yes, which kind?

There are different ways to ensure the highest iOS/iPadOS that your device will support is installed on your device.

This support article has instructions about updating an iPhone or iPad wirelessly --> Update your iPhone or iPad - Apple Support

You can also use Mac and PC computers to update system software, as outlined in this support article --> Update iPadOS - Apple Support

Use this support article to identify your iPad model --> Identify your iPad model - Apple Support and then the list below to find out what your iPad is capable of running. Alternatively—and somewhat easier—is to simply try updating it and see if it will update. When updating, your device will update to the highest version currently available that it will support, or it will just say it is up to date (and can't go any higher) and won't install anything. If you want to run a higher system version than your current device will run, you need to buy a newer device.

These models are all able to be updated to the current version, iPadOS 17.0.2

-iPad Pro 12.9 (2nd generation and later)

-iPad Pro 11 (1st generation and later)

-iPad Pro 10.5

-iPad (6th generation and later)

-iPad mini (5th generation and later)

-iPad Air 3rd generation and later

For updating app software on a mobile device, follow this flow: App Store app > Updates, or select your icon in the upper right corner > click update all or scroll down past the first screen to select individual apps.

I want to upgrade my iPad

Well, just read the above post to learn how.