How would I remove ads which are posted in quickbooks online?

You can't do anything more  than click the x.  Even then, they just come back.  

Hi there, Barry.

I'll provide details about removing the displayed ads or pop-up tutorials in your QuickBooks account.

These pop-ups were designed to guide and suggest how you can optimize your QuickBooks Online experience. While the option to permanently turn off these pop-ups is currently unavailable, you can dismiss them by clicking on the X icon or the No, thanks! as an alternative way.

In addition, there are many tips and video resources available you can use while working with QuickBooks in the future. You may refer to the following link to learn more about QuickBooks Online and how to use it effectively: Learn about QuickBooks Online with how-to videos.

If there's anything else we can help you with, please feel free to reach out to us anytime. We’ll be right here to answer them for you.