How to put address book from my old company email into my new one

I am moving my email from a server at my previous employer to my account at inmotionhosting. I have exported the address book as a csv file and cleaned it in an ASCII text program. I have also successfully imported the csv file into roundcube in my inmotionhosting webmail account. But now I do not know how to proceed. I want the address book to link outlook on my laptop to my inmotionhosting email account but do see any instructions on how to do that. I have two email accounts – one at my previous employer (who has let me keep that account until I no longer need it) - and my inmotionhosting account.

Email addresses that come in through my inmotionhosting email account are still added to the address book on my old company server when I create a new address. They then reside on the old server that I want to leave. How do I proceed to get my address book onto the new server and off the old one?

The old company server is a Microsoft Exchange server and my inmotionhosting account is an IMAP/SMTP account