Regarding IP address

Suppose I have 10 computer connected with one internet modem via LAN. Then What is happened?

  1. 10 computer shows 1 IP or
  2. 10 computer shows 10 IP.

Please inform me.
Thanks

Both options are possible, but for 99,9% of modems installed at home it will be option 1. The network knows how to keep the computers apart via the NAT protocol.

If it is using IPv6 then it is possible that 1 computer might use 10 different IP addresses. It is only with IPv4 that IP addresses are in short supply and would be shared between different uses/computers.

Of course most home networks are still using IPv4 although any current hardware should support both.