The meaning is that everyone can drink coffee here AND that It is usual /normal for people to drink coffee here. So the most accurate translation in my opinion is: "You (in the sense of "one") can drink coffee here." "It is possible to drink coffee in this place." "können" = be able to, can "dürfen" = be allowed to If you want to say "You are allowed to drink coffee here."/"It is allowed to drink coffee here" you should use "dürfen"--> "Man darf hier Kaffee trinken."