How to Add Multiple Banner Ads?

Hello,

I am trying to add 3 ads to the top (or on the side, but close to the top), of my page. It looks like a “footer sidebar” is only available, which places the ad link to the very bottom of the page, which isn’t very helpful. How do I add three banner ads to the top? And where do I find the widget or plugin to do this? My page is: https://www.isaacmeyers.com/

Thank you!