I’d personally avoid consuming pre-made shakes. They’re promoted as weight loss and fitness supplements, but the fact is that a lot of them are loaded with unnecessary amounts of sugar and carbs. Unless you're burning all of that off through exercise, you're not going to lose weight. Companies have to load them up with sugar or else most people wouldn’t bother drinking them.
I’d personally recommend making your own homemade smoothies and shakes. I’d recommend getting some classic smoothie ingredients—like fruits, berries, coconut water, soymilk, cacao—and learning some tasty smoothie recipes. Combine them with an unflavored whey protein isolate and you’ve got yourself a low calorie shake that should help keep you lean and healthy.