Making a two-column post in Twenty Eleven Theme

Hi – so I have an issue. I want to make the twenty eleven layout a two colum layout thru and thru. For those who dont know, even when you select the two column layout – individual posts are one column. So I pasted the sidebar on the post page template and I see the sidebar – but now I am having trouble modifying the CSS so everything views correctly.

I want this page https://bloometernal.com/demo3/i-love-my-son/ to look like this one https://bloometernal.com/demo3/. HELP!