lost my android phone, how do i find it

On a Samsung, try Samsung's own Find My Mobile too, using your Samsung account. Sometimes it shows a location when Google's doesn't, and it can turn on the phone's battery saver from a distance so it lasts longer. If you think it was stolen and not dropped, call the carrier and get the SIM blocked. Ask them about blocking the IMEI too.

Google's Find My Device (it got renamed Find Hub on newer phones). On any computer or another phone, search for it and sign in with the same Google account the lost phone uses. You'll see it on a map if it has a signal, and you can ring it at full volume even on silent. If it's somewhere you can't get to, use Secure device to lock it and put a message with another number on the screen. Only use erase as a last resort, after that you can't track it any more.