How to find and replace a word in my text?

This is a question that warrants your further reading of the Pages User Guide for Mac section on Find and replace text in Pages on Mac - Apple Support. If the question pertains to Pages for iOS, Pages for iPadOS, or Pages for iCloud, you can find those respective user guides at Pages - Official Apple Support.

Click in the text of the document.

Press command-F to open the Find and Replace pane.

Type the word you want to replace in the Find box.

This should present a number telling the number of times the word appears in the document, and should highlight the first occurrence of the word in yellow and other occurrences in grey

Type the word you want to replace it with in in the Replace with box.

Click Replace All to replace all occurrences of that word.

OR    Replace and Find to replace the highlighted copy then find the next occurrence of the same word.

OR    Replace to replace 'this occurrence only.'

OR    <   or    > to move to the previous or next occurrence of the word.

Regards,

Barry