Combining address books and transferring contacts and saved emails from Win 7 to Win 10

I have Live Mail 2012 and a comcast.net (Xfinity) mail account on my Windows 7 pc.  They are pretty much interchangeable--I can get email both places.  But...my address book is not the same.  How do I get them the same AND how do I transfer the address book to my new Windows 10 pc.  I will only use my Xfinity (comcast) account on my new pc.  And how do I transfer saved emails from my old pc to new one?  Thanks..

I tried several things mention this page.  Copying all addresses to me doc but that did not work.  Highlighted all address but they would not paste into email.  Also tried to save as csv file but could not even find the app launcher to get that process started.  Help!

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