Which type of milk should I get?

Can anyone help me out and explain to me like I’m 5 the difference between A2 milk and protein milk? And also fairlife milk? Or is that protein milk? I’m not lactose intolerant or anything. I just need something a little easier on my stomach and easy to digest but also preferably high in protein and I can’t figure what’s the difference and which one is better for me. Hopefully a good balance of high protein and easy on the stomach if that exists? I used to get fairlife but recently been getting the A2. I also prefer whole milk for which ever one I get. This milk would be for drinking and foods like cereal, oatmeal, not a for an ingredient like in a cooking recipe.