How do I get my contacts on my new iPad?

Contacts are stored in iCloud or a 3rd party email account. Either log in to the iCloud account used on the old device, or add the email account to Settings->Contacts->Accounts and turn on the Contacts option.

Link-> Use contact accounts on iPad - Apple Support

Ensure that you have enabled Contacts in iCloud in iPad settings for both your old and new iPad:

Settings > [Your Name / AppleiD] > iCloud > Contacts - set to ON