To test the working of our GitHub configuration, we'll use ssh, which tries to make a connection. We'll use the T flag, followed by the URL we want to connect to you get at git@github.com:
ssh -T git@github.com
This is going to test our connection. It will make sure that the SSH keys are properly set up and we can securely communicate with GitHub. When I run the command I get a message saying that The authenticity of host 'github.com (192.30.253.113)' can't be established.

We know that we want to communicate with github.com. We're expecting that communication to happen, so we can go ahead and enter yes:

From here, we get a message from the GitHub servers as shown in the preceding screenshot. If you are seeing this message with your username then you are done. You're ready to create your first repository and push your code up.
Next, we'll move into GitHub, go back to the home page, and create a new repository.