Disabling 'Add Sections' on a page so you can edit it before going live

Hello - pages are public unless they’re disabled or password-protected but how do you make an 'ADD SECTION' element hidden whilst you are working on them in a live site...... ie hiding new pics, galleries, buttons, layouts, text etc....

Is this possible...?!

Basically how do you hide/disable new sections to a live site whilst you're updating or adding items...

THANKS 🙂