Different LaTex templates can be used to change the structure and design of your LaTex documents. For example, there are templates available to create resumes, cv's, articles, theses, and other types of documents. Both Overleaf and Authorea allow you to search for templates shared on their platform. When writing an article for publication, you can also often find LaTex templates for specific publications on the publishers webiste or by contacting them.
Here are some of the places you can find freely available templates: