Unfortunately, the Surface Laptop 7, including the 13, 13.8 and 15 inch version, doesn't feature support for active digitizer pen input. It only supports finger input. You can also use the ordinary capacitive pens without pressure sensitivity and other benefits of the active digitizer.

As you can see on this official link, active digitizer pen input is missing from the specs sheets of the Surface Laptop 7: https://www.microsoft.com/en-us/surface/devices/surface-laptop#tech-specs-uid66f1

The confusing part is that the older Surface Laptop 1, 2, 3, 4, and 5 versions do support active digitizer pens, so its lack on the Surface 7 is a downgrade.