Let's make sure we are talking about the same thing. There is technically, no such thing as a "wireless Internet". The Internet is very much wired. How we connect to the Internet is another story, but it is always via a "network" connection first. And then that network must connect through a "gateway" device, typically a cable/DSL modem.
So are you able to log into your local network, just not out to the Internet? Or does your wireless not work at all?
Please note too that marketing weenies have made things worse by coining the term "wireless router". Routers are wired - Period. End of discussion.
So called "wireless routers" are really "integrated" devices, that is "discrete" network "appliances" or devices consolidated on to one circuit board and stuffed in one case with one power supply. A "wireless router" contains in the same case a wireless access point (WAP), a router, and typically, a 4-port Ethernet switch. Some makers produce "wireless modems" - a product that includes the "gateway" device as well - convenient when it they all work, confusing when not.
In any case, even though we may be talking about one piece of hardware, which part of that hardware you are having problems with is what matters.
Are other computers on your network (everything on your side of the gateway device or router) able to access the Internet? Can you access your router's or WAP's setup menus via your browser?