Nothing.
If your iPad has been stuck on iOS 10.3.3 for the past few years, with no major upgrades/updates forthcoming, then you own a 2012, iPad 4th generation.
A 4th gen iPad cannot be upgraded beyond iOS 10.3.3/10.3.4 for WiFi & cellular data models.
A 4th gen iPad is a NEARLY 8-year old device, now!
These old 8 and 9-year old iPad models are too old, now, too underpowered and completely incompatible with any of the current and future versions of iOS/iPadOS.
Soon, your iPad model will be fully and completely obsolete by the end of 2020.
Sorry, but it is what it is, now, in 2020.
Here’s why.
Tap and read my link below for my additional info about your iPad model.
If you own OLD 8 and 9 Year Old iPad mo… - Apple Community
Sorry and Good Luck to You!