How do i become admin to my router

If you own the router, go to their support page and lookup the default login/pass. If that doesn't work, you may need to do a hard reset. If you do a hard reset, you'll lose all current special settings if any are applied.

If you don't own the router and are renting it from your internet service provider, you can contact them with necessary changes. Perhaps they'll give you an admin login/password.

Factory reset your router by sticking a bobby pin into a small hole meant to do exactly that, wait a few seconds, connect RJ45 cable to your PC and voila, now you have full control over your device.