Here in the UK, we have betting shops on every High St. We currently have 8700 of them, so every probably does mean every - there’s probably not a town in the UK without one. They are predominately associated with horse racing, but you can go in and place a wager on basically any sporting event, and a lot of non-sporting ones - you could probably bet on whether it will rain tomorrow if you liked.
Away from the High St, anyone can open an online account with a betting exchange - which will offer more sophisticated gambling options such that you can act as your own bookmaker etc
So how does this all work in the US - when I worked there (in Pennsylvania) I didn’t see any betting shops, and I gather betting is much more tightly regulated. So say I’m living in Philadelphia, and I want to place bets on the weekend games, e.g. Penguins v Flyers, Grizzlies v 76ers. I also fancy Strong mandate in the Kentucky Derby later in the year, and I’d like to put a bundle on me and the missus seeing our ruby wedding anniversary. What are my options?