If all you need to do is send a postcard or a letter, there’s no need to visit a post office. Pretty much any kiosk will sell you stamps, just make sure they’re the right value for what you’re sending and where. Once you’ve got your stamps licked and affixed, drop your mail in any post box. These are the small orange boxes attached to buildings around town. Don’t put your mail in the dark green boxes with round holes in the sides. Those are trash bins.