I would like to tell you beforehand that I am not judging you here or influencing you in any way. It is your own decision as to what kind of food you like to eat. As you said that protein is useful for our life, I would like to tell you that if you eat meat only for protein, then you will get many types of things in vegetarian food which give more protein than meat. Meat will give you protein but it will also give you dangerous things like cholesterol. Yes, a person cannot eat the same food every day but there are many varieties available in vegetarian food also and if a person wants to become a vegetarian, then it will be the easiest for him here. Nowadays I see that people become non-vegetarian for taste but if we look at vegetarian food, there are so many options that you will not even be able to remember them.