Webpack is a bundler. As the name suggests we bundle all our sources together into one file and we no longer need all these script tags. Now we dont need to worry about multiple issues coming up and from where with all our script tags, it will all be gathered from one source. Also webpack will compress the files and make the code easier and cheaper to manage.
So we generally dont pay too much attention to webpack because things like create-react-app will have it all pre done for us and our package.json is ready to go with the basic package. However, without this it is not too hard to get a webpack up and running. First you need node, and once you have node you can use the node package manager to install webpack.
Then you would want to run webpack and attach it, most likely, to your root file. Then when you run your program webpack will run with it and bundle what you need.
Now when you want to use webpack or add things to your webpack it is quite simple. Using webpack can be done in a variety of different ways. We use it all the time without even thinking about it (or at least I do). Any time you might be trying to use an image
...and you use require, you are using webpack. You might remember using this require() function with many things, such as modules, or as I showed in the image, images. If you are coding in node, I am sure you are familiar with requiring axios. For me it is similar to using import with react files.