Da capo means 'from the beginning' and is usually indicated with. D.C.. above the last bar. It can be inserted with the repeats-menu.
During playback, a fine mark will end playing when the melody is played from the beginning once more. An optional coda (anything behind the DC-sign) will be played
Da capo is a simple case of the more complex dal segno construction; the missing segno implies the beginning of the tune.
A da capo in the main part will be added at same time position in accompaniment parts