Enlist, pick a job that is valuable on the outside, and then take classes in off duty time.
At the end of the enlistment contract, if you don't like the military, you can get out and be happy you have life/job experience and (hopefully) a degree to get a job you like in the civilian sector, with little to no out of pocket expenses.
If you also don't like your job you had in the military or didn't go to school while in, use your GI Bill to get training/attend school in a field you do like.