I am joining the military and need help structuring a plan to build muscle!

Hi everyone. I’m a 21-year-old female, 103 lb, petite build. I’ve been interested in getting stronger and building muscle for a while, even before deciding to join the United States Marine Corps. Now that I’m officially joining, I want to make sure I’m training in a way that actually prepares me physically and helps me build real strength.

My main goals are to build muscle, get stronger overall, improve endurance, and develop strength in my arms, legs, and core. So far I’ve mostly been consistent with arm-focused workouts, but I do have leg and ab routines planned as well.

My current arm routine (3 rounds, 10–15 reps each) includes hammer curls, Arnold presses, lateral raises, bent-over rows, and tricep extensions. For abs, I’ve planned bicycles, in and outs, leg raises, planks, Russian twists, and flutter kicks. For legs (also 3 rounds, 10–15 reps while holding a weight), I’ve planned lateral lunges, lunge pulses, plie squats, crab walks, and jump squats.

Is this split the best approach or should I switch to only full-body workouts 3–4 times per week and focus more on compound movements. How much cardio should I include if I’m trying to gain muscle while also preparing for military fitness standards?

I eat normally when I’m hungry, but I’m open to nutrition advice as well. ◇Thanks in advance◇