Something I have wondered about is how can a layman like me could communicate with a satellite? I would need an antenna of some sort I believe but then what's the protocol?
There are amateur radio satellites that you can legally communicate with using a technician’s license and equipment for around $100 (essentially a UHF/VHF FM walkie-talkie and an external antenna, i.e. just analog voice).
If you have a fairly modern iPhone, you can already share your location to a satellite out of the box.
And if unidirectional communication counts, you already do it every time you use GPS :)
Most of satellites you don’t talk to, the satellite repeats signals. People talk to each other, mainly to make contacts, using the satellite.
It is also possible to talk to ISS.
1: https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weat...