Considdering that The Oscars are being broadcast on ABC, which is widely broadcast OTA, really, the simplest way to get this would be to stick a classic antenna onto your TV and watch the OTA broadcast. Assuming you're in a viable place in North America at least.
I wish I'd realized 'Oh crap, I coulda just used an antenna' before I missed the Toronto Santa Claus Parade because Global put the live stream behind a pay wall.