New ipad
How do I separate my new iPad mini 5 from the old iPad mini 4 because I would like to clear all information from the old one
iPad mini 5, iPadOS 14
Question marked as
Simply erasing a device from settings will not impact data stored on other devices:
Settings > General > Reset > Erase All Content and Settings
If your intent is to decommission your old iPad prior to disposal, or giving it away, you should follow this procedure:
What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support