How to update to 13 without a computer and no link to update

That model corresponds to a white 64GB iPad with retina display, also known as an iPad 4.

An iPad 4 cannot update beyond iOS 10.3.3. It simply does not have the hardware to support newer versions of iOS past iOS 10.

If you want iPadOS13, then yes, replacement will be necessary - or continue to enjoy what you already have, accepting that it cannot be updated beyond its current version of iOS.

Your existing iPad lacks the necessary CPU and RAM capabilities that are prerequisite to running iPadOS.

Winnerwonder wrote:

Does this mean that I am forced to buy a new iPad despite the fact that my iPad is functioning?

Only if there's something specific you require from iOS 13.

If your iPad works, without iOS 13, then why do you assume you need to buy something else?

If you do require iOS 13 for some reason, then yes, you will need to buy a newer device. An iPad Air 2 or later will be capable of running iOS 13.

Also, its important to note, that an iPad 4 is 7 year old hardware at this point. In mobile device time that is a life time.

What model of iPad do you have exactly? Settings->General->About->Model?

Are you sure it can actually update to iOS 13?