How does “upload” work?

This is related to another topic I’ve posted. I’m not a code-literate person. I just want this blog to work without much effort. What I would like to do is upload some pictures to a post. I go to the “upload” section of the post editor, I upload my pics, they appear in the browser. However they don’t show up on the finished product. They don’t even show up in the viewer at the bottom of the editing screen. I was able to use some code to insert one photo with the help of a poster to my previous topic. However, this isn’t what I want. I want to be able to post my photos with captions without needing to learn a new language.

Somebody please help me!