There is no option to sue site builder on pages. Older forum threads show tabs, but there are no tabs to choose from anymore, there is 3-dot menu on the left side that opens the page options that lets you switch the editor, and page builder is not listed.
Example of what older forum threads show:
Example of what I see:
I’ve created the home page for this site using sitebuilder (my theme has a “Home” section under Appearance). If I go to edit the home page under Pages, the site builder shows up and I get the usual wordpress page editor. Just not on any other page.
Hi Zong
Thanks for reaching out.
If you’d like to use the classic interface in WordPress 5.+ please install the Classic Editor plugin. Alternatively, if you’d like to use the new Block Editor interface you can insert a SiteOrigin Layout or SiteOrigin Widget block.
Let us know how that goes :)