Last issue first - as this appears to be the actual problem that you are attempting to resolve…
If your iPad is unable to join your WiFi network - and the error message suggests that the WiFi Password is incorrect while other devices can connect to your WiFi network - very often the easiest remedy is just a restart of the WiFi Router itself.
To restart you home router, disconnect power - then wait at least 30 seconds before restarting. When you router has rebooted (which may take several minutes), force-restart your iPad:
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:
- Press and quickly release the volume button nearest to the top button.
- Press and quickly release the volume button farthest from the top button.
- Press and hold the top button.
- 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.

This should resolve your issue without the need to reset the iPad.
If you do wish to fully reset your iPad - in so doing clearing the iPad of all data, settings and installed Apps - you can easily do so without affecting any other devices. From iPad settings:
iPadOS16 and later
Settings > General > Transfer or Reset iPad > Erase All Content & Settings
iPadOS15 and earlier
Settings > General > Reset > Erase All Content & Settings
A more extreme [and generally unnecessary] method would be to follow this procedure:
What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
Either of these two methods will reset the device without any impact to other devices - but be aware that manually removing data or files may be be replicated to other devices that are signed-in with the same AppleID.