It’s public information by federal law. If it wasn’t in the public’s interest to know the data would not be available.

This is available on any of countless websites that publish public transponder information.

I use this one to look up interesting planes I see above me: https://globe.adsbexchange.com/

Planespotting is also a major hobby, so you can find websites devoted to pictures.

You can also get an rtl-sdr dongle and collect data directly from planes, sharing it with others on adsbexchange. Fun!