In order to edit code, you must have a Business plan or higher.
How to Add Adot Pro's Code to Duda
To edit the Code, click on code editor in top right navigation area.
Paste the Accessibility Indicator code after the opening <body> tag of anywhere at the top of code.
Then scroll down to the bottom of the page and paste the button code within the footer before the closing </div> tag.
And You're Done!