Getting an error while running rest api in HTTP request activity

Hi everyone,
I need to connect to a web service(Rest API) which asks for a client certificate and a password in HTTP request activity. but I cannot find where to get client certificate and password.
Without filling client certificate and password, It throwing an error (" The underlying connection was closed: could not establish trust") as below.
Any idea on how to do it? It would also be good to know how to do it with http request.

Can you explain the scenario which you are trying to do @MVenkataiah?

If you are calling the request which is https, you need to add the certificate ;

Thank you HareeshMR for your response.
Will post more details on my request soon.