Phone a friend! Go to a friend's house and run nmap (zenmap for a GUI if you like, https://nmap.org/download.html https://nmap.org/download.html most common OS

Phone a friend! Go to a friend's house and run nmap (zenmap for a GUI if you like, https://nmap.org/download.html https://nmap.org/download.html most common OSs supported). Do the same for them in return. You might also like to explore this: https://www.shodan.io/ https://www.shodan.io/ and if you have some time on your hands this: https://www.kali.org/ https://www.kali.org/