My Internet isnt working on my LapTop

hey,
I got a Laptop for christmas and got the internet working, yesterday but then i tried to install my webcam, the webcam was not built in the laptop i plugged it in, and now the internet doesn't work is it because i installed the webcam rong ? what should i do? i really want internet. when i got the internet working (the first time) i called called the comany and they showed me step by step. when i found out my internet wasn't working i did those steps all over agin but stops me in the middle saying somthing isn't right. so please, can you help me with my problem?
thank-you