After Updation to iOS 14 WiFi got slow

If a forced-restart of the iPad does not resolve the issue, network connectivity issues can often be simply resolved by a reset of the iPad Network Settings:

Settings > General > Reset > Reset Network Settings

Reset of Network Settings will not result in loss or deletion of any data.

Try a hard reset of your iPad by holding down both the Home and sleep/wake buttons simultaneously until your iPad goes to black and restarts with Apple logo, then release the buttons.

Good Luck!