I’m taking “does not open” to mean it won’t power on. If you meant something else, tell me what you see when you press the power button.
Quick checks first
Charge it for at least 30 minutes with the original charger on a different outlet. Check that the charging light or port is working.
Hold the power button for 30 seconds, then release. Wait 10 seconds and press it once.
Unplug everything else (USB devices, docks, external displays) and try again.
If it powers on but the screen stays black, connect an external display. That tells you whether the problem is the panel or the whole system.
Warranty service order: Sign in at account.microsoft.com/devices, select the laptop and check its warranty. If it’s covered, create a service order there, and Microsoft arranges the repair or replacement without you needing a local shop. Register the serial number first if it isn’t linked to your account.
Authorized Reseller Customer Service Centers: Call a center before visiting to confirm it handles Surface Laptop 7, because some only do inspection and recovery. Back up your data first if the laptop can still start.