Please provide a link to your site.
The whole site, or selected sub areas can be made full width using their align area dropdown list “Align Full” option.
for example, the whole site wrapper “Align Wrapper area” option can be found in
Customize (in WHERE mode) > Wrapping Areas > Wrapper Area > Wrapper Area Alignment and spacing
For the site, you can also just set the site width to a large number like 10000px