Solution:
For dotnet language is not supported for fido token, as it is based on the supported browser (currently only Google Chrome). For now, it supports javascript API functions.
The easiest way to use U2F in a supported browser is to use the u2f-api.js library, which exposes two functions:u2f.register : Register using a U2F device.
u2f.sign : Authenticate using a U2F device.
