Which would be better, going to the military as a officer or join the sheriff Dept as a correctional officer?

From my take on how you describe things about yourself, I think you would be extremely bored as a Correctional Officer although you could have a regular life. But I don't think you want or are built for a normal boring day after day life. As soon as you mentioned the Rangers I say Military. As far as those "orders" you mentioned, you sound intelligent and mature I believe you will find a way to deal with them. Life is supposed to be an adventure, go live it. Godspeed.