It sounds like you mean you made a page to have a format with a left side and right side. To add content to the left/right side sections, go to Pages > Right Side (the default right side, or whatever you are calling it), and the same for the Left Side. You can also create new left/right side pages - just choose Content Type to be Side Right or Side Left. You can also filter pages on the List Pages, to find the Side Right / Side Left pages, and then edit them. Choose which ones are default on the edit page for each. And on the Edit Page for the full page (actual page) which has the formatting that includes the side right/left, you can choose if you are using the default side right/left, or a specific one.

If you have any further questions, please feel free to ask.

You can just hit enter to start a new paragraph, if you don't know html coding.

For ads, it is good to use the Ad(d)s app; here is the tutorial: https://www.ultimatewb.com/adds-app/adding-google-ads-media-plugins-analytics