Help for a friend who wants to supplement meals

Ntdrkyet

Hey everyone, I have a male friend who is looking to eat healthier and supplement some meals with protein shakes. He is 32 years old, 6'2" about 250lbs and is looking both to slim down and add muscle mass. Any helpful pointers I can give him? What kind of protein is best? how often can he supplement with just a protein shake? He has an active job and is picking up running thanks to his competitive son. Thanks in advance,
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