Help with black space in sidebar?

I’ve been posting on my website and I noticed that the right part of the site has a huge empty space that could be used perfectly for displaying images at high resolutions or a sidebar.

My question is how can I modify the space used by the body width post images to fit better?

And how I add a sidebar with wadgets, and how I add wadgets

In this screenshot the poster is using manual line breaks. You can write until the end of the line, and the line breaks are automatic.

Text looks very strange indeed when you break the line
on the middle
of the


Yes, i just using manual line breaks, But anyway the space in the right continuing being too large
Images are cut off above 700 pixels wide.

The right gutter is used for the vertical timeline. You can adjust the width a bit using CSS if you like, but I strongly suggest using CSS media queries to control the sizing to ensure the browser has enough width.