You have identified a first generation iPad Pro 9.7" - for which the last available update is iPadOS 16.7.10.
While Apple continues to release occasional point security updates for major security issues, your iPad is very much within its twilight for system software updates. When security updates cease, as emerging security vulnerabilities are not patched, your iPad will become increasingly vulnerable to exploit.
While your iPad will continue to have utility for a number of years, you might be well advised to consider replacing with a much newer model. Be aware that for your own safely, some websites and online services (in particular financial and banking) may no longer permit use of devices that no longer receive security updates. App Developers may also drop support for older devices over time.
For information, here is a list of the highest version of iOS supported by all models of iPad (for simplicity - “generations” are shortened to a number) that are restricted in their ability to be updated:
32-bit devices (obsolete)
iPad1 - iOS 5.1.1
iPad2, iPad3 and iPad mini1 - iOS 9.3.5 (WiFi Only models), iOS 9.3.6 (WiFi+Cellular)
iPad4 - iOS 10.3.3 (WiFi Only), iOS 10.3.4 (WiFi+Cellular)
64-bit devices
iPad Air1*, iPad mini2 and iPad mini3* - iOS 12.5.7
iPad Air2, iPad mini4 - iPadOS 15.8.3
iPad5, iPad Pro (9.7"/12.9" 1st generation)* - iPadOS 16.7.10
iPad6, iPad Pro (10.5"/12.9" 2nd generation) - iPadOS 17.7.2
(*) obsolete
Newer models are all able to be updated to the current version - iPadOS 18.1.1
- iPad Pro 13" (M4)
- iPad Pro 12.9" (3rd generation and later)
- iPad Pro 11" (1st generation and later + M4)
- iPad Air (3rd generation and later + M2)
- iPad (7th generation and later)
- iPad mini (5th generation and later + A17 Pro)