Is It possibile editing the page’s with a free account?

Hi, I'm new with WordPress, I'm trying to add a JavaScript code to the page without using a plug-in. I find out online that's possible but all the images I found are different from what I have.
For example in appearance section I have only three options, I don't have theme file editor.
So I'm guessing that maybe it's because I have a free account. Someone can help me? Thanks