Are those protein shakes healthy?

ForTheMostPartYesBut: That's like asking "are those cars safe?" You must check out the details, called ingredients. It also depends on what you'll want to get from the shake. If just protein, then there are whey products, pea products, rice products, dried egg products, etc etc, and combinations. Past the protein are all the vitamins, minerals, herbs, and extracts. It's complicated. For pure protein I prefer egg whites