How to add Maj7 chord in Mac?

[dflat]

thanks...is there any manual that tells me all the short cut?

In the menus, you will see key commands for some of them. Usually you can type in a song's chords mostly using the computer keyboard:

- is minor
Return to move on to next beat
^ for maj
use letters and numbers names for chords/chord qualities (lower case is ok)
/ for inversions
cmd-B for preceding barline (add shift for after)
cmd-D for preceding double (add shift for after)
cmd-R for preceding repeat (add shift for after)
n for N.C.
w for invisible chord quality(used for bass line Cm/F ... /Eb ... /D etc.)
cmd-Delete for deleting beats
cmd-\ for inserting beats

you can also hover the mouse of an icon. If it has a key command, it will show.