My iPad is not showing that the latest update is available, how do I get the update?

If you own a 2019, 3rd gen iPad Air 3, then it is too far behind in iOS/iPadOS upgrades/updates.

If you have access to a full computer, like a Mac or Windows PC, try either using the Finder on a Mac that has the newest macOS Catalina installed OR with an older Mac with an older Mac OS, download and install the latest iTunes version ( or latest iTunes for Windows PC ), make sure the Mac or Windows PC is connected to the Internet, connect your iPad by the USB charge cable to the computer and let the iTunes application upgrade/update that iPad model, using the iTunes Software Update feature, to its current, maximum of iPadOS 14.7.1.

Make sure your iPad is, at least, charged to 50% or greater to attempt this.

Also, make sure to do a backup of your iPad's data, prior to upgrading/updating. Backup to Apple iCloud and/or a full Mac or Windows PC using the same iTunes app OR if a newer Mac, running macOS Catalina, or later, making a backup using the macOS Finder app.

If NO access to a Mac or Windows computer, you will have to seek help from a good friend or family member to help you out

OR

Search online to locate and call contact your nearest, “local” Apple Store location to try/attempt to make an appointment to get your Apple iPad upgraded/updated to its latest iPadOS 14.6.

Apple Store employees will be glad to help/assist you.

Best of Luck to You!

An iPad Air 1st generation cannot support iOS versions beyond 12.5.4, because of hardware (CPU/RAM) incompatibility, sorry.

Regards

Giulio

A 2013 iPad Air 1st generation is 8-years old, now.

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