The number one for me was running games at decent game shops. But I’m spoiled by several.
Second has been by going to conventions, running games is best. There are many cons that will comp you a ticket or even a room share if you run enough games. Local cons are best, but the previous sentence applies less to them unless your lucky and nearby the big ones.
Facebook has been incredible, search for your city name and D&D or dungeons and dragons, or use your state or region name in a search too.
Meetup has been good too.
Wizards store locator is kinda good for finding stores running AL, depending, some stores post up they have games when they don’t, but many do have games. So try a couple few. Actually shop for a decent store, don’t just accept the nearest one.
I realize cons are probably all on line now, but local ones may still have online games with decent contacts. Also the issue with stores not being open or not running games, still they may have contacts in the local area and or be part of a Facebook or meetup group.
good luck!
what region are you in?