Question

what stage do most stars spend the majority of their lives in?

Answer 1

It a stage known as the "Main Sequence" stage. Stars achieve nuclear stability at this point and remain in this stage until the end of their lives.
Have a nice day!

Answer 2

Out of the 7 most important stages a star spends about 90% of it's life in the "Main Sequence Star" stage. In this stage a star forms helium in it's core by fusing hydrogen atoms. Actually the Sun is in this stage right now. How long it stays in this stage depends on the star's size.