Well well well , first of all buddy, u should have post this in bodybuilding thread instead of opening up a new one, similiar thread has been emerge and closed,. Anywhere to answer ur question, since ur goal is to gain weight so i assume that u wan to bulk.

TO BULK
-u need extra calories intake.
-supplement cant help u if ur diet is not proper.
-if u only eat 3 meals a day, trust me, u will be owas running ard at ur starting line. U wont go anyway. AGAIN take more calories, break it into 6 meals.
-eat 1g of protein to /lbs of ur bodyweight.
-Possible, Eat "real" food (eggs, meat, milk)

Can u take whey on non workout day?
- ask u a question, can u take meat on non workout day?


A friend told me that whey is much cheaper than if I were to spend on the same amount of protein gained from cooked food. True?

Erm... this is not the way u save ur money ><

By the way dude, try to read the sticky that we have it on our H&F for why u r not growing, diet plan and etc. There is bunch of infor for ur micro and macro intake needs.