Hi Adrienne Merrill,
Thank you for reaching Microsoft Community.
You may use this link to check details of your Surface device Check Warranty Page - ROBO SelfServe Portal (surface.com). Or you may also view the details of your Surface device on your Microsoft account under devices. If you haven't register the device yet, you can add the device with the serial number.
If this answer your question, we highly encourage you to inform our Community by clicking on Yes or marking my post as an answer.
Kind regards,
Lavenia