Hello mbtdinc2 and welcome to the Community!
Connecting your bank accounts and credit cards within the bank feeds of QuickBooks Online is a huge time-saver. It means you can add or match your transactions directly from the feeds and will make the reconciliation process a breeze. Let me go over why you're being asked for an "Identification Word" as part of the connection process.
When you go through the steps to Connect bank and credit card accounts to QuickBooks Online you'll be required to enter the username and password that you use to connect to the online banking portal for your financial institution. Some banks require additional security checks in addition to your username and password. The "Identification Word" you're being asked to enter is a word that you would've set up as a security measure with your bank. If you're not sure what the word is, check the security settings in your online banking portal, or consult with your financial institution.
Once connected, you'll be able to get started categorizing your transactions. If this is your first time connecting a card, I want to share a fantastic article that has all the steps you'll need to become familiar with this process:
Categorize and match online bank transactions in QuickBooks Online
Let me know if there's anything else I can give you a hand with.