Using Digital Object Identifiers for referencing in Pages

Because Apple has kept Pages and its document format closed source, there are no third-party applications that interact with the application beyond copy/paste. One exception is EndNote, and then only because Apple commissioned a third-party to write an EndNote Pages plug-in that would allow the transfer of content into Pages from EndNote. That was last updated in Nov 2023.

DOI references are used in Word document citations and cross references when following certain reference styles (e.g. APA, MLA, or Chicago). Apple's Pages is not a Word clone and has no cross-referencing capability or included templates for the mentioned reference styles.

You would be better off using MS Word where support for DOI exists.

How do i add Digital Object Identifier (DOI number) into my bibliography - APA 6th style?

Can you better explain what you mean by digital object identification for referencing? Historically in the Pages community, it is not a term I have seen mentioned previously.