First I assume y0u are able to access the internet on a computer hard wire into the router.
Can you address the router setup page over the wifi or not? See your router book for more details however the most common possible addresses are either 192.168.1.1 or 192.168.0.1 .
In other words we need a lot more details concerning your problem.
Hell is this a new set up or one that is just now is giving you a hard time and the questions go on and on.................