I don't sing very well, but many people have told me I'm a good actress, and I enjoy acting. Do I have to sing well in order to be involved in live theatre, though? It seems like most of live theatre is musicals.
Not all theatre is musicals. It's just the Broadway shows that break box office records are musicals—and they get all the publicity, so it makes it seem like most of live theatre is musicals.
However, it will help if you know how to sing…because then you can get a lead role in a musical and people will see and remember you and you can get some big breaks.
If you want to be in a musical, singing lessons are a great idea. They'll make you into a much better singer. Until you develop the lungs and talent for a musical, however, you can try speaking on pitch.
You speak your lines (not sing), but you say each word on pitch so your voice rises and falls with the melody. Kind of confusing–but it happens all the time….even in big Broadway performances.
Break a leg!