Although exercise is the best way to do that, there are other ways.
Practice controlled breathing exercises, which are easy to do from the comfort of your home.
One is where you take a few small breaths in and one large breath out. Keep doing this.
Breathing exercises are also relatively easy to find on the internet.
both are true :) bmi cannot tell the difference between fat and muscle because it is based off your height and weight only
No more then 35% should come from protein on a daily basis.