Hi there, I'm Tim and will be assisting you today. I have over 15 Years as an Engineer and have been with eBay, DoD and many others. I will do my VERY BEST to help you. If you like i can offer remote access and a call. In addition, with any positive rating I will support your question going forward for free.
It probably does not have the network drivers installed.....Do you have the factory disk? Who makes the computer, what model? If no disk, you may need to download the drivers on a flash drive and then install t hem to get online.
That explains quite abit, We need to do a step be step walk through via phone to see what kind of NIC (Network interface card) you have, and then work on finding drivers.