There's a few YouTube channels that provide live feeds of LAX. They operate a few times a week, usually during the late morning to early evening hours pacific time.

Airline Videos: https://www.youtube.com/c/AIRLINEVIDEOS LA Flights: https://www.youtube.com/channel/UC7WAqB7dyv1t8jKunD-8krA

There's also ones at ORD, ATL and occasionally other US airports. I've seen a few popup in other countries too, but can't seem to find them in you YouTube history.