My 1st generation iPad Pro won’t update to iOS 12

Try upgrading/updating your iPad Pro connected up to your computer running iTunes and see if it will let you upgrade the iPad that way.

Perform a backup of that iPad to iTunes on the computer before you begin the upgrade.

Best of Luck to You!

Go into the Settings App, General Settings panel.

In the right hand column, tap Storage ( and iCloud Usage, if still using iOS 9 or 10 ).

At the top in the first block of 3 panels where it is titled at the top of this block Storage, tap the panel that says Manage Storage.

A list of every app will generate itself.

Once this list stops generating, look through this list until you see something like iOS 11/12w.x.x in this list.

Tap on the gray disclosure arrow at the far right on that iOS 10/11.x.x panel.

It will bring you to another screen that will allow you to completely delete/remove the entire iOS upgrade/update, if one exists.

Let me know what you encountered.

What happens when you try?

What do you mean no option?

What happens if you try using the Software Update in the Settings app?

Do you own a real computer with an up to date iTunes version on it?