Tags / Group names for new items in iPhone

How to assign /add the existing logins and other records to those various predefined groups, which can be seen here: 'Home' / '+' / 'New Item'
How to use them?
How are they different from the Tags?

Thank you.

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1Password Version: 8.10.0
Extension Version: Not Provided
OS Version: iOS 16.2
Browser:_ Not Provided