Hi @RobertaPell,
I just wanted to quickly add one potential caveat to the info @ryan_corris provided. If the module item is truly just a plain external URL, everything should work as Ryan stated. Since you mentioned the link being to an eBook, it may be the case that that link it actually an external tool launch URL, which will pass aloneg data form Canvas when clicked to authenticate users to the eBook platform. If that is the case, I don't believe you'll be able to replicate that URL and launch process with a link in a page. I figured this may help out in case Ryan's advice didn't work (and for other people who may come across this thread in the future too).
-Chris