If the texts are similar, the heading you want to link to will usually appear at the top ... if you export it as a PDF or EPUB document. You can even create a table of contents for your Google Slides.

Different formats can also make managing several documents cumbersome. Combining these documents into a single PDF file may be helpful for personal or professional use, to deliver simplified, ...

Pick Save as PDF to choose a filename and destination, and you can even add password protection to the document if you want to. There's PDF functionality built right into Finder as well.