If you want to lose weight is it better to stop alcohol if you drink a lot of beer?

It would help a lot. Alcohol has a lot of calories. So cutting out alcohol would do you no harm and would be a good way to cut down on calories. One 12-ounce can of beer has about 150 calories. Multiply that by the number of cans you drink and you'll see how many calories you eliminate. If you're having a hard time quitting see your doctor or an alcohol counselor.
Yes. Alcohol is empty calories. Each 5oz drink is about 250cal so to lose one pound per week, you need to decrease 500cal/day. Avoiding or decreasing alcohol is a simple way to lose weight and your gut.