See the Code for definitions, but basically....
(1) In a government building;
(2) In a courthouse;
(3) In a jail or prison;
(4) In a place of worship, unless the governing body or authority of the place of worship permits the carrying of weapons or long guns by license holders;
(5) In a state mental health facility
(6) On the premises of a nuclear power facility,
(7) Within 150 feet of any polling place,
Walking into bars, or stores to pay, or even to shop is perfectly fine unless you are told to leave and then Not leaving could be a criminal trespass (same as in any other state). Thankfully, bars in Georgia are few and far between; TGI Fridays is not a bar, nor is anywhere else that's open on Sunday and serves food.
Note on churches, it's an unauthorized location unless the governing body permits firearms.