I've been doing it for about two months, can someone give me pointers on if its good or bad?

2 days/week: Upper Body
2 days/week: Lower Body

Abs/Upper Body Exercises:

3 sets (8-12 reps): Dumbbell Curl
3 sets (8-12 reps): Tricep Extension
3 sets (8-12 reps): Lateral Raise, Shoulder Press
3 sets (8-12 reps): Bench Press, Dumbbell Fly
3 sets (8-12 reps): crunches, reverse crunches

Thats 8 exercises, so 24 sets. Total work out time is around 40 minutes.

Back/Lower Body Exercises:

3 sets (8-12 reps): Lunge, Dumbbell Squat
3 sets (8-12 reps): Calf Raise
3 sets (8-12 reps): Straight Leg Deadlift
3 sets (8-12 reps): Bent Over Row, Lying Row

Thats 6 exercises, work out time is around 30-35 mins.

Is this a decent workout program? And also, for the time being (the next two years), I am unable to get a gym membership as I am at school and work all day (6am - 9:30pm). Right now, I have some cardio equipment but for weight training I basically have a bench and a set of adjustable dumbbells. All the exercises I mentioned above are done with just the dumbbells.

They are good, but I am sure I am missing out on something. If I had to get the next thing to add to my gym, which equipment do you recommend?

Also, I don't usually have anything prework-out and post-workout I usually have a banana, and thats about it. Any recommendations there?

My primary purpose for weight lifting (for now) is weight loss (I also do 3 days HIIT, 1 day steady state cardio). In two months, I've lost approx. 20 pounds of weight, so its going ok for now but I would like to optimize my workout.

Most people who are just beginning weight training and are trying to loose body fat benfit most from a total body workout 3 times a week and sticking to heavy basic compound lifts: squat, deadlift, bench press, bent row/pullups, military press.