Hani Hijaz

hi to all forum mates, I am a newbie to this informative forum based on NCH Software Recording Products. I am recording my stuff on wavepad v 5.9. How to record/overdub my vocals with the mixed music track. 2 channels recordings. Means I must hear the music track and recording my vocals at the same time. It must be very simple but for me it seems difficult how to begin and where to click?? Love to all forum mates, Hani HIjaz Newbie