Hello sunnycool,
You have everything you need just need couple of extra hands
just kidding you can use your sound card line in all you have to do is connect the line out of your mixer in line in of your sound card and then in sonar record them one by one playing live what I will suggest is record the tabla first so you can record rest of your performance in timing with your tabla voice track can be done in last in sonar all you have to do is play your melody using harmonium or Yamaha (dummy) then when you sing you will know your cue then erase that dummy track, I hope I have not confused you much.