Turning a 2 column to a single column layout

This is a two part question. The first part is that I want my 2 column layout to turn into a single sectioned page, when hiding the 2nd column on mobile, everything centres which is what I want - however I can’t make this happen with my tablet preview.


Here is my site Read-Only:
https://preview.webflow.com/preview/theknowledgefoundationconcept?utm_medium=preview_link&utm_source=designer&utm_content=theknowledgefoundationconcept&preview=9409118dcd2ac5a8bd8fe41c9188d1d6&mode=preview

If you refer to tablet landscape it will not work. Tablet landscape is presentet as a normal web page

I’m not sure I understand your answer. If I have made one of the columns is hidden in the tablet landscape view - wouldn’t it mean that I have a full-width sectioned website?