How to make a page show when a checkbox is ticked

This article explains it all in detail:

https://pdfautomationstation.substack.com/p/check-boxes-that-show-and-hide-pdf

You can't hide a page, but you can delete it.

To make it work, you need to create a template from second page:

Select 'Organize pages' tool, select second page (the one you wish to show/delete), on the toolbar select 'More' then 'Page templates' give it a name, like: Tax 

then uncheck the little checkbox next to the name of the template to make it hidden.

Close Organize pages tool, and as 'Mouse UP' action of checkbox, use this:

if(event.target.value != "Off"){
this.getTemplate("Tax").spawn(event.target.page+1, false, false);
this.pageNum = event.target.page+1;//delete this line if you don't want to jump to template page when spawned.
}
else
this.deletePages(event.target.page+1);

If you need to rename fields on a spawned page, change first 'false' to 'true'.