So why not add one? You can't magically turn a wired ethernet card/port into a wireless one, you need either a wireless add-in card for your system or a wireless ethernet bridge device. If you've got a laptop your cheapest solution will likely be one of the many USB wireless devices, but if it's a desktop you have the option of a PCIe card which will have better range and overall performance at the cost of being harder to physically install.
I've been fighting with my network card for two days now and thought that maybe I could get some help here.
The problem is, after opening the device manager window and choosing "network cards" all I can see is "Marvell Yukon ... Ethernet Controller". And I need a card for wireless connection.