In WordPress, page builders have become extremely popular nowadays. A page builder is a tool that allows you to create complex layouts made up of rows and columns. Most modern page builders have front editing capabilities and are usually drag and drop. Page builders lets you edit anything between the header and the footer of your site.
Popular Page Builders
People often confuse a templates with a theme. Although very similar, templates live inside a theme. Often you can buy a template for a theme. For example you can search “Divi templates” and you will get countless results but none of those templates will work if you do not have Divi Theme installed.
A theme, like the Divi theme or the Beaver Builder theme (note that both of these also have a page builders) allows the user to control the entire layout of a website and also style at a global scale. You can style all of your fonts for the headers and paragraphs, also input modules like buttons and forms etc…