iPad Air 2

If restoring or reseting your iPad, there will be no detrimental impact to other devises signed-in to iCloud with the same AppleID.

If, however, you attempt to manually delete data, doing so will likely affect other devices - as changes/deletions will be synchronised via iCloud.

Restoring or resetting to factory settings will wipe all data and settings from your iPad. It is, however, possible to reset iPad settings without erasing locally stored data.

To simply reset your iPad settings:

Settings > General > Reset > Reset All Settings

For a full reset of your iPad settings, erasing data:

Settings > General > Reset > Erase All Content and Settings

Restoring to Factory Settings will wipe everything - and install a fresh copy of the most recent version if iOS/iPadOS that is supported by your device:

Restore your iPhone, iPad or iPod to factory settings – Apple Support