Redirecting url

I was trying to redirect my blog from .com/blog/ to simply .com. When I tried to redirect my whole homepage came apart and the coding is now broken. For instance when I access the .com/blog/wp-admin/ none of the tabs are connected and now each (i.e. Dashboard, Write, Manage, etc) leads to a “the webpage cannot be found” page. Could someone tell me how to reverse this and then what I need to do to have my blog be .com rather than .com/blog/.

Thanks