auto insert word in place of code

Hi All,

I have no idea what to use to search for this so hoping someone can answer.

I want to know if it is possible to have a command around, or before a particular word in my webpage that will then auto fill that word into other multiple positions on that page.
example, i have multiple pages for different suburbs for computer repairs services. The sentences will have the suburb in it, i want that to auto change or fill at multiple points in each page from a selected word according to the placement of some code. I want it to auto fill that same word where i place code.