Speaking only of the U.S.A.
Individual states have Governors who by executive order have said Masks are required in various places. It is not a Law. Laws are made / passed by Congress whether it be State or Federal and signed by the Governor or President to make it an official Law. Executive orders from Governors or the President is an order not a Law.
Yes I wear a Mask in Public Buildings due to more than one underlying Health issue.
Rookie Scribe