You will find a keyboard like the one below in most instruments.
It is used to send Note On/Off events and can be played by either the mouse or a QWERTY keyboard. The bottom 2 rows starting A & Z do the lowest octaves with the A row being the black notes and Z row the white. The Z key corresponds to the note C on the keyboard. The rows starting Q and 1 are the higher octaves with the 1 row being the black notes and the Q row the white.
The keyboard is transposed up and down an octave by the +(=) or - keys.
In each instrument with a keyboard you will find a [Net] button. If you are connected to a collaboration this will send the note events played on the keyboard to all participants.