You are doing everything right according to you, but still you are not gaining muscle or losing weight. You are drinking 4-6 litres water daily. You are taking 4-5 meals. You workout for 1-1.5 hours daily. You sleep for 8 hours too. I know it’s frustrating to put efforts and not getting any results. So, here is something that you can do. So far you have been doing everything right. Now, you just need to do some additional things. Keep a tap on what are you eating in those four-five meals. Make sure you are consuming enough protein according to your body's need and dividing it equally through out the day. Start tracking the exact calories that you are consuming. Slightly increase or decrease the portion size of your food, depending on the goal. Keep a note of how much weight you are lifting in that 1.5 hours. With time try to increase either load, reps, or sets. Make sure you do this gradually and not aggressively. If you do all these additional things, you will achieve your goal.