"It's all about calories in and calories out."
No, it's not. It's about a lot of things.
A caloric deficit is only part of the equation.
"Should I go to the gym, 6 days a week, or 7?"
You should probably go 4 days a week, and murder it in those 4 days. If you're going to the gym 6 days a week for body composition change, you're doing it wrong, unless you have a LOT of muscle.