How does CAD draw an elevation from a plane?

First, define your floor plan as a block.

Then enter the command: xc.

Select objects: 1 found.

Select object:

Enter editing options.

[On/Off]/Crop Depth (C)/ Delete (D)/ Generate Polyline (P)/ Create New Boundary (N)]: External Mode-Objects outside the boundary will be hidden.

Specify the clipping boundary or choose the reverse option:

[Select polyline/polygon/rectangle/reverse clipping ]: r

Specify the first corner: Specify the corner:

It is very easy to follow the prompts step by step. You can intercept that part of the picture if you want. It is convenient to draw the facade. I always draw like this. I hope I can help you.