Text duplication question

[Renzakuken]

Good morning

I have a form I use regularly at work that has several segments where specific reference numbers are repeated.

These numbers are at not in a header, title or regular intervals unfortunately and appear in segments / paragraphs of text.

My question is if I set out what these numbers are on one page, how can I have them auto-filled in the required locations specified throughout the rest of the document?

Thank you
Jack