How to use the ssh command remotely connect to the server?

To Git Bash  and Ali cloud ECS cloud server  , for example, you want to make a remote connection, you can use ssh username @ server IP  to connect as follows: 

note:

1. When a password is entered without prompting

2. root is a super administrator

3. Connect the premise of success: the server opens the ssh service

4 may not be used the Git the Bash , turn to XShell  are possible like.