Controlling where sections show up and having multiple sections in a page

So the design I was given to develop, I need 3 sections: one in the main content column, one in the side column and one at the bottom (full width)

There is a code {%- for block in section.blocks -%} but that seems to always list the same section. Is there a way to create 2 new sections for the pagebuilder and how can I call them in the code? (like have section1.blocks, section2.blocks, etc.)

This is not possible, you can just catch the condition for it. Ex:
{%- for block in section.blocks -%}
{%- if block.type == ‘banner-bottom’ -%}

{%- endif -%}
{%- endfor -%}
So you can catch which blocks show up at the bottom, content and side.
Hope it helps!