To clarify, just because Carol Danvers might show up in Avengers: Infinity War doesn’t mean that she’ll have her Captain Marvel powers yet.
However, Captain Marvel writer Nicole Perlman recently said that she’s altering Carol’s origin story so it doesn’t resemble Green Lantern’s.
So while we will eventually see Carol flying around and shooting energy blasts as Captain Marvel, she may just be a normal Air Force officer in her first MCU movie.
One of the reasons for that could be that she’ll appear in another movie before her own solo adventure, and directors Joe and Anthony Russo may have accidentally let slip a few months back that Avengers: Infinity War will be that movie.