Thanks for posting in the community! If I'm understanding you correctly, you're referring to a shape with an added action that links you to another page. If so, you should be able to edit the text of this shape. In the example below, my box with "Default Text" is linked to Page 2 of my document. By double clicking on the text, I was able to edit it and then Shift + Ctrl + Click to go to Page 2. If it is the text itself that has the action associated with it, you should still be able to edit the text in the same way and the link will still be maintained with the new text.
If you're working with a shape that isn't behaving this way, please submit a ticket here with the URL to your document and a description of which shape's text you're unable to edit. Hope this helps!