Yes. "Crack a beer / crack open a beer" means to open a beer (informal). To my ears, "crack open a beer" is a little more common, but that might not be the same for speakers. Beer is non-count if you talk about it as one thing: "He drinks a lot of beer." "Germany is known for its good beer." Beer is countable if you talk about the number of drinks (bottles, cans, glasses) "He drank six beers."