Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hi
If the folders and contacts on the iMac are stored in your Microsoft 365/Exchange/Outlook.com mailbox, you do not need to export them. Add the same email account to Outlook on the MacBook and they should sync automatically.
If they are under “On My Computer,” they are stored only on the old iMac and will not sync.
The missing Export option is usually because you are using the newer Outlook. On the old iMac, go to Help > Revert to Legacy Outlook, then use Tools > Export to create an .olm file. Microsoft’s instructions are here: https://support.microsoft.com/en-us/outlook/export-items-to-an-archive-file-in-outlook-for-mac
Copy that .olm file to the MacBook and import it using Legacy Outlook: https://support.microsoft.com/en-us/outlook/import-email-messages-contacts-and-other-items-into-outlook-for-mac
After importing, the items appear under “On My Computer.” If you want them to sync between both Macs in the future, move the mail and contacts into folders belonging to your Microsoft 365 account.
If you tell me whether the old account is Microsoft 365/Outlook.com, Gmail, IMAP or POP, I can tell you which of these two methods applies.