If you want to add any widget code on your website, please follow these steps:
Edit your page on the front end by clicking on Boostly Editor or Edit with Elementor.
Hover your mouse over to the desired area you want to put the widget code
Then you will see three options on top with the names; Add Section, Edit Section and Delete Section
Click on Add Section
Then on the left side, click on this icon. (See image below)

On the Search Widget bar, type HTML.
Click and drag the HTML widget (Not the Custom HTML Widget) to the newly added Section
Then paste the widget code
Click on Update to save the changes
PS. Here’s a video on how to do it – https://www.loom.com/share/7b91afd967dd46f88922c2833c3c0d7c