How do I locate my lost Android phone?

Google's Find My Device (it's called Find Hub now) - open it in a browser on any computer and sign in with the same Google account as the phone. It shows it on a map if it's on and connected, and you can make it ring even on silent, lock it, or wipe it. If it's a Samsung, SmartThings Find is worth a look too. If nothing shows, the phone is off or location was off - it may still show the last location it reported, and it's worth checking again later in case it comes back online.