Unlike some years back when sites were almost exclusively static, the standard currently is to have a feature-rich, dynamic website. Few people can create this type of web site from scratch though, hence the simplest solution to have a dynamic site is to use a script application. A lot of hosting companies offer script installers which you can use to add this kind of an app for each of your domain or subdomains, so you will not have to set up anything manually. The main advantage of using an installer tool would be that the scripts are available to use in a few minutes and the copy that'll be set up is already with the settings required for it to run properly on the specific hosting web server, so you will not have to alter any script or account settings. That way you can quickly build one with only a couple of clicks even though you may have never had a website before.