It depends on the specific proxy software you are using. Some proxies support SSH key authentication, while others may only work with username and password authentication. You should consult the documentation for your specific proxy software to see if SSH key authentication is supported and how to configure it.
In general, if your proxy supports SSH key authentication, you will need to configure your SSH client to use the appropriate key when connecting to the proxy server. This can typically be done by specifying the path to the private key file using the -i option when connecting via SSH.
For example, if your SSH key is stored in the file ~/.ssh/id_rsa and the proxy server is listening on port 8080 of the host proxy.example.com, you could connect using the following command: ssh -i ~/.ssh/id_rsa -D 8080 [email protected]
Again, the specific details may vary depending on your proxy software and SSH client.