In some countries there are Security Businesses that will design, install, and maintain / monitor CCTV systems
No. There are other methods of connecting to the internet, such as cable internet and 3G.
No it needs an ethernet cable connection to an internet service
A modem uses the phone line to connect to the internet. This is usually slower than a wifi connection.
A telephone to connect to and a game for the internet.
You need at minimum, a telephone line.
The modem on your computer must connect to your Internet Service Provider's server over a land telephone line. You connect the computer's modem to a telephone jack as you would a telephone.
ATA or analog telephone adapter will automatically connected to the when is it connected to internet.
Cable Internet service, DSL, Fiber to the Premises (FTTP), Fixed wireless, Cellular Radio Network, Wi-Fi, Satellite Internet Service
To connect a telephone to the telephone port of your computer, use a telephone jack.
You need to connect a modem using the modem port and the telephone cable.
You could use the telephone port on your laptop if it has one, if it doesn't you can use its USB port to connect an adapter which allows you to connect to internet as long as there's cell service.
If there is no telephone lines then you can not connect to internet by phone. I presuppose there is no wireless networks neither. So if you want to connect to internet in place like that you can do it by satellite phone, but that is expensive option.