Extemd, Get Out, Retrain

Early 20s, single no dependents, first job, in a job I neither like or dislike but leaning towards dislike (medical). Signed for 4 years, contract ends in a year. Got stationed near home but joined to travel, discover my passions, and self growth.

Not sure if should still stay in because I don't hate the Air Force, I just dislike my job (long hours, shiftwork, working holidays, no 3/4 day weekends and I never got any TDYs or deployments under my belt.

Should I extend a year, retrain to a different career field (not sure what career field but I am looking for something that is exciting, get to travel.

If I do get out I want to to go to college but don't know what to major in and what job to choose.

Please assist!