The Input menu, in the menu bar, lets you choose different input sources (such as French or Japanese), open the Keyboard Viewer and Character Viewer, and gives you quick access to preferences and help for the input source you’re currently using.
The Input menu appears when you do any of the following in Keyboard System Preferences:
Enable two or more input sources.
Select the “Show keyboard and emoji viewers in menu bar” checkbox.
Select the “Show Input menu in menu bar” checkbox.