linode lish console
Take a look at our guide on Using the Lish Console
When you see
localhost login: you'll type root, which is your username.
Then you'll see a Password: field, type the root password you set when you created your Linode.
Keep in mind that when typing your password, you won't see any output - this is for security reasons. You can also paste your password into Lish if that's easier.