Re: Practice shooting
One of the best things about a .22 is that you don't need a long range for it to make you look you have no idea what your doing. 200yds on a gusty day is more than enough.
Learn range estimation, land nav, stalking and observation.
Old school land nav, map and compass, it smokes allot of people, learn it and practice it, it is a skill that diminishes, if you're good at it, it will set you apart.
Don't stalk people, it may well get you in trouble, just pratice moving thru terrain quietly, and with minimal enviromental disturbance. Try hunting, if that's an option and interest, don't do it just to train, if you keep your shots short you'll have to be stealthy. If not hunting try wildlife photography, same stalking skills are involved.
Learn to be very attentive/observant, car or anything else, goes by, try to get the color, make, model, plate number, distinguishing marks/items, speed and direction, instead of just it was blue.
Also FYI the services are not what they once were, they don't take screw ups and they don't give marginal characters MOSs that allow for independent thought. No crime, especially drug an alcohol related, or violent, they probably won't even talk to you. Keep your grades up, it matters.