Manufacturer’s Warranty (included when you buy the device) covers defects in materials and workmanship —but it does not cover screen damage that resulted from accidents or physical impact. That includes cracks, broken glass, pressure damage, etc.
If you had Microsoft Complete coverage at the time of purchase — which must be purchased around the time you bought the device — it does include coverage for accidental damage, including cracked screens.
With Complete, you can open a claim online, and often Microsoft will repair or replace the device for a service fee/deductible rather than full replacement cost.
If you never purchased Microsoft Complete when the device was new, then this coverage won’t apply now — and screen crack won’t be covered under the standard warranty.
Visit:
https://support.microsoft.com/devices
Sign in with the Microsoft account that you used to register the Surface.
Find the Surface using your serial number.
Click “Repair my device” and follow the instructions to submit a service order.