Copying "Contact" Lists In Outlook 365

I HATE setting up a new computer!!!

With that in mind, I'm struggling to establish contacts/email address as I'd had on my old computer's Outlook 365. Both new and old computer (no longer available) are/were using the latest 365 Office software. What I am trying to replicate is the ability to begin typing a person email address in the TO area, and having suggestions appear. NOTE: I believe that Outlook somehow records addresses used, and these may be part of what drives Outlook to make "suggestions". Though obliviously not all used email addresses appear as a "contact", I'd love to have this data available for use in "suggestions"....but on to my initial issue...

I found some "contacts" files which, despite my low tech abilities, I managed to import into my new computer's Outlook (see attached photo). However, I now have three (3) "contact" lists as shown, with only the second and third list containing any entries.....and those entries, while having some similarities, are different.

Ideally, I'd like to have the contents of the second and third list combined, and be available within the first list. BTW, when I create a new email, I get no suggestions presented from either of the two lists which contain entries.....I get nothing!

MANY thanks in advance!!! Michael