in a page / post editor you can set that individual posts Content Container to Full Width:
You can also use the Layout Element to do the same thing, but using its Display Rules you can define where should be full width eg.
Pages -> All Pages or even
This option sets the page container to 100% and removes all of the Themes Container Padding.
You should then use the GenerateBlocks plugin to add Container Blocks to create each full width section of that page. This allows you to define padding and inner container widths for each section, whilst having full width backgrounds.