SketchUp only has one model space, and it can’t be divided into multiple viewports within a single scene.
Layout is the tool to use for creating multiple viewports within a single page.
BUT, if you want to fake it within SketchUp—then essentially you need a strategy which has your model duplicated, with the copies orientated into new positions, and set next to the original (so that they all share the same common model space within a scene).
Copy 1 = plan view
Copy 2 = front elevation
Copy 3 = side elevation
… and, again make sure that all copies are arranged close enough together so that they share a common screen space that gets used for one scene.
This sort of workaround works pretty well if you use instances of a component for your multiple copies.
Each instance can be rotated into the correct orientation, and a section cut can be applied to it. so that you can get the cross sectional view your looking for.
… and in a similar manner—if you just want to have 2D cross sections in multiple orientations, then look into the command ‘Create Group From Slice’ which is found on the right click context menu (of a selected section cut). This is a great command to use for extracting 2D contour outlines from the position of the active section cut.
There no need for multiple copies in this approach because all of the desired cross section positions can be made from the same component instance. However once you make one, you’ll need to move them (and orient them) so that they collectively create the multiple viewports effect which your looking to do.
Alternatively, going along with the entire Layout methodology… You simple create multiple scenes within SU… each representing the viewport orientation you want to have.
And then use Layout for what it’s designed for. Drawing all of your viewports, positioning them on the page, and linking each one to the specific scene which you’ve created in SketchUp.