My Gym Program

Hello everyone, my name is Ali (Male) I am 19 years old and 75KG with around 18% body fat. I have been going to the gym now for about 4 months using the program I have typed down below. I go 6 days a week, training 2 body parts a session with abs sometimes. My workouts lasts around 90 mins and 120 mins with ab workout if included sometimes. One day I would train chest and triceps, the second day I would train back and biceps and the third day I would train legs and shoulders and then repeat the three days once again to make it 6 and then the 7th day on Friday is my day off. My question is, am I making the most out of my time at the gym? Am I over training a muscle group? maybe under training a muscle group? I am asking these questions as I am not seeing much results and I am not sure if I am giving it my all. Feel free to ask my any question and I will reply right away.

I make sure to use weight that make the last few reps of each set a little difficult to achieve and my diet is not on point at all times but I do prioritise as much protein a day as I can.

CHEST
Bench press 4x10 (1x20KG, 1x40KG, 1x45KG, 1x50KG)
Chest press 3x12 (1x10KG, 1x12.5KG, 1x15KG)
Incline Dumbell Bench 3x12 7.5KG OR 10KG
Cable fly low down 3x12 14KG
Seated Dip 3x12 38KG
TRICEPS
Cable 3x12 (1x7KG, 2x9KG)
Cable pull down 3x12 (1x16KG, 2x18KG)
Cable over head 3x12 18KG
Barbell skullcrasher 3x12 15KG

BICEPS
Dumbbell curl 3x12 10KG
Barbell curl 3x10 15KG
Seated hammer curl 3x12 7.5KG
Both hand dumbbell 3x12 10KG
BACK
Deadlift 5x12 (1x20KG, 1x40KG, 1x80Kg, 2x100KG for 6 reps)
Pull down wide grip 3x12 (1x27KG, 1x32KG, 1x36KG)
Pull down close grip 3x12
Seated row 3x12 (2x15KG, 1x20KG)
Pull 3x12 (1x32KG, 1x36KG, 1x41KG)
Lower back 3x12 10KG

SHOULDERS
Lateral raise 3x12 10KG
Overhead press 3x12 10KG
Shoulder push up machine 3x12 (1x10KG, 1x12.5KG, 1x15KG)
Lateral raise machine 3x12 25KG
Plate weight 3x12 10KG
LEGS
Squats 5x12 (1x40KG, 1x45KG, 1x50KG, 1x 60KG)
Leg press 3x12 90KG
Leg extension 3x12 34KG
Back thigh machine 3x12 38KG
Calf raisers 4x12 20KG