Depends really on how experienced you are. 20 sets of chest is a lot IMO.
Personally, my chest workouts never exceed more than 12 sets or so.
How long does it take you to complete this workout?
Been working out for almost a year already. I can only do 165 for 6 to 8 reps so im still a begginer.
12 sets only? I feel like my chest wont be sore with 12 sets.
Takes me about 1h 15 to 1h 30 max. Should i less the sets and go heavier on the weights?
Yeah man, other people touched on it but I would say that this is too much volume but there isn't a way to tell for sure. Some people progress with a lot of volume. Stick with what you're doing for a few weeks and see if you progress. A year of dedicated working out would still be considered beginner for most lifters.
The way I track progression is to see if I can increase my PRIMARY lift for that particular day every week.
For example, primary lift for chest day = Bench Press, primary lift for leg = squats, primary lift for back = bent rows, primary lift for shoulders = military press.
I go in the gym every workout and use that first primary exercise to see if I can increase the weight (by 2 to 10 lbs)
With that in mind, keep continuing to do what you're doing. See if you can increase that 165lb bench to 185 within the next few months (or weeks if possible). If don't see any progression in your lifting numbers, then you either aren't eating enough or your workout isn't effective.
Me personally, I've been lifting for 4-5 years, and 12 sets of chest is more than enough. If you're intensity is at 100% per workout, 12 sets should be enough to break down all of your chest fibers. Push yourself and don't do weights that are comfortable. Each weight should challenge you. Every single set that I do, I make sure that last rep is brutal.
The goal isn't to get X amount of sets in a workout. The goal is to break down the muscle in the gym, then replenish it with proper nutrition and rest.
EDIT: Here's the workout I have been doing for chest.
Bench Press 4x6-8
Incline Press 3x8
Flat Flies 3x8
Dips 2x15