If you are rich of a good singing voice then you have a good chance at being hired as a singer, given you make efforts in the right direction. If you want to be a playback singer, then all you have to learn is how to sing, as playback singers are pre-recorded. They are never seen on film, as the actors lip sync to the pre-recorded tracks. Man, just create audition tapes to demonstrate your range and your ability to perform Bollywood style songs.