Cordova offers two development paths for mobile app development. The first is cross-platform (CLI) workflow, which allows your mobile app to run on multiple platforms with very minor code modifications. The CLI is a high-level tool that eliminates most of the lower-level shell script functionalities. Go with this development path if you don't need to develop an app at a lower level or if you want to get started on learning how to create one on Cordova. The second is platform-centered workflow, which allows your mobile app to focus on a single platform and develop it at a lower level. Go with this development path if you want to work at a lower level script.
Plugins are essential to Cordova. They provide a vast amount of tools in addition to an interface, native components, and bindings to standard device APIs. Creating a Cordova project does not have any plugins to begin with, so you'll have to add any manually by yourself. Thankfully, Apache Cordova has their own set of plugins called Core Plugins, which provides access to a smartphone's device functionalities.