Hi there,
GenerateBlocks doesn’t have the capability to set the width of your container, as the container is controlled by your theme.
Ideally, the theme you’re using needs to have a template or option to set the page to full width (as GeneratePress does).
Let me know if you have any more questions regarding this. If you believe there’s a bug, please feel free to open a support topic with more details so we can investigate.
Thanks!