How long does it take to gain 2 lbs of fat, not water or musle, fat? the same approximate 1 week it takes to lose? under typical, normal conditions?

Weight gain: The typical thought on this is that every 3500 kcal excess consumption is one pound of weight gain. So on average, if you consume 3000 kcal per day and burn 2500 kcal per day, you will gain 1 lb in 1 week (500 kcal excess per day). The opposite is also true. To gain 2 lbs, you would need to consume 7000 kcal greater than your expenditure.