PROTEIN SHAKES

i have gotten so confused from trying to figure this out from the internet. so i'm asking my fitness pal community. my brother in law drinks a protein shake( from gnc ) he mixing it with sugar free-silk almond milk, he told me to drink this one hour before lunch and one hour before dinner and then eat a healthy meal.he works out and i do not. should i follow this plan to help me feel full . he has lost about 50pds
thanks for any advice
dancerpurple