Are those hosts managed by the vCenter server? If so, we don't need to connect directly to them. If they aren't and you need to connect directly to them, the credentials here will normally be credentials you can use via SSH rather than ones you would use to connect to vCenter.
As for the vCenter, can you confirm the configuration of the server itself? Is it set to go to port 443? When you click on the vCenter server from the Data Sources list and click Validate, does it give the green check?
i tried with ssh credentials and now host works, and yes, the vCenter is validated(green check)