I do not have a computer to update my itunes. How can i update my ipad to the latest ios?

A 4th gen iPad cannot be upgraded beyond iOS 10.3.3/10.3.4.

This is a 7-year old device, now!

Its internal hardware is too old, underpowered and completely incompatible with any current and future versions of iOS.

Sorry.

If you want/need an iPad that can run the latest and greatest versions of iOS, as well as, the most current, up to date apps available, then, you will need to purchase a new iPad from Apple or a discounted, refurbished iPad from Apple’s Refurbished & Clearance section of Apple’s Website.

Best of Luck to You

What iPad model do you own and what is its current iOS version?

Settings > General > About > Model and Version