Wired or wireless connection? I assume you mean wired cable. A really cheap and often easy way is adding a  USB WIFI dongle. Drivers install and using the WPS or auto connection settings on your modem and the wifi dongle. 
they can be tiny and cheap
The drivers suggested are specific to the hardware of the Network card 
- In Windows 10, type system info in the search bar on the taskbar and select the System Information option in the search results.
 - In the System Information window, click the + symbol next to Components in the left navigation area.
 - Click the + next to Network and highlight Adapter. The right side of the window should display complete information about the network card.
 
Mine for example is Name    [00000001] Killer Wireless-n/a/ac 1535 Wireless Network Adapter
(On a dell laptop)  Google and driver was offered 
Have fun. Your trying which makes you a lot better than most. Recycling an old computer makes you rock in my view :)