How can I setup Outlook on my iMac running OS X Yosemite Version 10.10.1?  

I use hotmail and no matter what I do I have been unable to get emails that are sent from my account to show they have actually come from my @hotmail.com account.  All emails I send from my account show up at the other end as having come from my wife's @hotmail.com account rather than mine.  If the recipient hits 'reply' it goes back to my wife at her account rather than to me.

I am guessing I need to delete my hotmail account on my iMac desktop and then setup Outlook, but perhaps there is an easier solution for fixing my sender ID problem.

Thanks!