Putty SSH connection with private keys

[Gatet]

To establish an SSH connection to a chipset, a private key file must be used.

The SSH library used (see attachment) provides a way to pass this key. However, at the moment I cannot find a way to associate the key file provided by the vendor with the available .net array type definition input, either as a file path or as a string with its content.

It would be very helpful if someone could help me here.

Thanks in advance!