iPad unable to locate printer

Do you have any security Apps (such as Norton) or VPN installed on your iPad?

If so, these may be interfering with your iPad's internal routing table - and may interfere with AirPrint/AirPlay/WiFi Hotspot or other Apple services. If present, it may be necessary to temporarily remove such Apps from your iPad - and then perform a forced-restart.

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

If you continue to have difficulties, check to see if your iPad is using the WiFi Private Address feature. This feature is intended to provide additional privacy and security when using “public” (untrusted) WiFi networks.

Settings > WiFi > [Your WiFi Network / SSID] - tap the “i” icon - Private Address

The Private Address feature is largely unnecessary for your home WiFi network; if enabled, Private Addressing can cause issues if specific MAC addresses are expected by your WiFi Router. You may need to disable this feature - and can be enabled or disabled for each individual network.

Use private Wi-Fi addresses in iOS 14, iPadOS 14, and watchOS 7 - Apple Support

Your printer and iPad must be on the same Wi-Fi network.

Connect an AirPrint printer to a Wi-Fi network - Apple Support