The Realme Narzo 10A is a better phone as it gives better specifications.
Processor: The Realme Narzo 10A comes with the MediaTek Helio G70 processor whereas the Samsung Galaxy M01 comes with the Qualcomm Snapdragon 439 processor.
Camera: The Realme Narzo 10A has a camera of 12 MP + 2 MP + 2 MP with F1.8 aperture whereas the Samsung Galaxy M01 has a camera of 13 MP + 2 MP with F2.2 aperture.
Check Full Device Specifications Realme Narzo 10A vs Samsung Galaxy M01
No, the Samsung Galaxy M01 doesn't support WiFi calling as of now but it would get it through a software upgrade.
The device is just launched and every newer Android phone would be getting it as this feature is in demand amongst users.
Check more about WiFI calling-
Check Full Device Specifications Samsung Galaxy M01