How to Insert a text box

I’m not sure if “text box” is the right term, but sure seems like it would be. I want to include a box of text within my post with the main text wrapped around it. A place to add information outside the regular content, hopefully with a different background color.

I searched for plugins but wasn’t finding quite the right thing, and most everything I looked at required inserting CSS code or something. Is there something more simple I can use in the visual editor?

Thanks!