Hi, EmrSrr00!
Thanks for reaching Microsoft Community and posting your inquiry. The Surface Pro 6 has a microSD card interface capable of reading and writing SDXC cards with UHS-I read/write speeds. Its mimimum capacity is 32GB and can hold up to 2TB.
You may also check this page to learn about SD cards are compatible with Surface.
We hope this helps you out, we highly encourage you to inform our Community by clicking on Yes or marking my post as an answer. This will help other members who may have the same issue as you. Otherwise, don't hesitate to update us so we can further assist you.
Kind regards,
Janette_Z