Says I have a connection, but no internet?

[highflesh371]

Hey so my family just moved houses and we had to change ISPs and so the new people came in and set up the internet and everything. So my problem is when I hook the modem directly into the computer my computer gets internet, but when I hook my modem to the router and the router to the computer it says I have a connection but when I connect I don't get internet. My router is netgear. I feel like I've tried everything I've even tried to go into the cmd and reset the IP and stuff but I'm not sure what to do. Please help.