As you had completed the initial setup, you will need to ensure that the Activation Lock associated with your Spouse's AppleID, you would be well advised to run through this -process - after which the iPad will be completely reset:
What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
These support pages should get you started with setup of your new iPad - and the methods of transferring your data from old to new iPad:
Set up your iPhone, iPad or iPod touch – Apple Support
Transfer data from your previous iOS device to your new iPhone, iPad, or iPod touch - Apple Support
Use Quick Start to transfer data to a new iPhone, iPad or iPod touch – Apple Support
If the donor iPad, from which you are transferring your data precedes iOS12.4, QuickStart will not be available.