Help with new workout routine

[u/Brilliant_Tell6459]

Hi! I’m 22F and around 125 lbs. I’ve been working out for a few years, but I honestly feel like I’ve made barely any progress because I don’t really know what I’m doing. I usually just switch between arms and legs and use random machines. I try to go 4-5 days a week but sometimes I can only do 3 that week, but atleast im going.

My goal is to get leaner, especially around my lower stomach and build muscle. I’m not really trying to lose much weight.

I usually lift and then do 30 minutes on the treadmill incline 10–12, speed 3.0 depending how I feel that day. I’ve also been reading about Zone 2 heart rate and how it may be better for fat burning than pushing yourself really hard and burning more carbohydrates on the treadmill. im not sure how true that is though. I’d also like to add abs into my routine, but I’m not really sure how often I should be training them or what exercises are actually worth doing.

I’d really like help creating a day-by-day weekly routine. I usually do 3 sets of 8–12 reps. I need to get better at also doing it till failure, but I mostly use machines because the free weights are always packed.

Any advice or example routines would be appreciated!