In order to edit the "Welcome" popup, please go to Dashboard > Templates > Popups
Locate the "Welcome/ over 18" popup and click on Edit with Elementor:
Please check these guides for further information:
Guide to Vamtam Elementor Builder
Next, click on the "Save options" icon and select "Display conditions":
Here, you can remove the popup from the homepage or add it to whichever post or page.