How can you duble the use of a modem&is it posible?

Definitely if you are planning on hard wiring all 10 computers you need to purchase a hub..Basically you would use one of the 4 ports on your modem. Run ethernet from router to hub input and add up to 16 computers. Over 16 you need a switch. If you are going to have some wire and the others wireless, you just need to security access code from the router,that you should have from the first wireless set up.You should have a setup disk for router if you didn't complete initial setup. Or contact manufacturer to get a replacement disk. As long as all 10 computers have wireless capabilities you just have to enter the access on each individual computer to access your wireless network.