Start with Stop Bleeding ⎮ Save Lives (21 min, PrepMedic), then Treating a Bullet Wound⎮Gunshot First Aid⎮ (23 min, PrepMedic). All 274 lessons here are free, from the teachers' own official uploads. You'll need first aid kit, cpr training manikin, trauma shears and a few more basics (about $160 of kit). The book to keep beside you: Emergency Care and Transportation of the Sick and Injured by American Academy of Orthopaedic Surgeons..