a. What is connected to my L.A.N. is my phone, my mom's phone, my computer, my mom's computer, my ps4, our google home, our wii, and our tv/cable box.
b. I learned that all my devices connect to the internet through a modem/router.
c. I would say be careful because wifi providers will try to scam you based on the cable. They say that it will go faster but it won't.