Transcript
Here in the Settings is a media option – what this basically refers to is that images in your Media Library.
WordPress creates these default sizes, and this just makes it easier for you to select them from a dropdown list, when you are placing images in your content.
Generally, you will find these won’t get changed and also this tick box is handy for organising the images on the server into month and year.
It makes it a bit easier to manage if it is not yourself, then maybe your web developer as well.
So, yes, WordPress will output your image at all these sizes including the original and you can utilise these in your content as I say. That doesn’t really get any more complicated than that.