New keyboard or keyboard replacement

Hi,

 

One of the keys came off of my keyboard on my Inspiron 8200. I am not tech savvy and cannot figure how to put it back on for fear that I will mess up other keys. Can anyone tell me how to do this.

 

Also, I have an extended warranty. Do you know if its better to just do a new keyboard or put the old key back on.

 

Thanks.

 

Missy