What is your PC currently connected to and how? If you go straight to a modem, then you buy a standard wireless router. If you're connected to a wired router, you add a wireless access point to that. If you want others to connect through your PC, what you'd need is a wireless network interface device that can act as an AP and be bridged to your wired NIC. In any event, I think you're looking for an AP and not a router unless you have some other purpose here. Maybe if you could explain more about your plan, it would get you a better answer.
Hi everyone! I was wondering if there was a USB dongle that works like a router. That I can plug it into my computer, which has a WLAN connected, and it will become an access point for WiFi. Basically a router that is as small as a USB flash drive. Thanks to those who help!