Generally, what does seeing a red star usually indicate about its mass and evolutionary stage?
Answer
A very long-lived, low-mass star or a massive star near the end of its path
Red color typically signals either a very low-mass star burning slowly for long timescales or a massive star that has exhausted core hydrogen and expanded into a cooler red giant.

Related Questions
What property of a star does its color primarily reveal?Which type of young star is intensely blue?According to stellar classification, which type stars are the hottest and bluest?What color was our Sun when it formed approximately 4.6 billion years ago?Why do colossal, massive stars burn their fuel at an astonishingly high rate?How do the lifespans of a hot blue star (30,000 K) and a cool red dwarf (3,000 K) generally compare?What technique do astronomers use to date star clusters based on color evolution?What does the absence of extremely hot, massive blue stars in a cluster usually imply?Generally, what does seeing a red star usually indicate about its mass and evolutionary stage?Why do brilliant blue light sources dominate the brightest detections in an active stellar nursery?