Open Question: Best way to use MRM whey protein isobolic for weight loss?

Hi All, I’m a pretty big guy 330 pounds x-college football player with an athletic build however during the past 2 years I put on some pounds due to eating bad choice foods and not exercising. For the past 2 weeks I have been working out, treadmill and mostly pushups along with avoiding fast food and making better choices when it comes to food. I’m planning on purchasing whey protein isobolic and substituting dinner with the whey mixed with milk, ice, Greek yogurt and either blue berries or strawberries or maybe even a banana to make a shake. However I wanted to know how many times I should take the shake in one day. I only planned on taking it once a day for dinner but I was considering also for breakfast and just having a decent lunch. Any help from people that have used this product would be really helpful, I am mainly looking to drop down in weight and just get a bit cut up.