CAD user confused

Hi all i am coming from SolidWorks and i have issues about dimensions example in solid work i can just make a square like an plane here and then extrude but the issue for me is here i can’t example go mesh mode and click on A and B and set the distance between those 2 or at least i duno how. Would appreciate help?

   D  .__________. C

I PPPPPPPPPI -------- Plane
A. ------------------. B

Blender isn’t a CAD program. You will be a lot happier if you just stop expecting it to behave like one.

When you say set the distance of course the easiest would be with a numeric field and the addon would do that but in regular blender you can display edge length (N properties) and then in edit mode you can scale and the edge length updates as you do.

Learning the methods of using the pivot point to scale in different ways is going to be much more useful to you in future Blender projects.

Or basic method, G G 1 Enter/Left click, G X “distance”, same principal with custom transform orientations.

Regarding the comment about scaling, you don’t even have to move your cursor. Just set pivot point to Active. Make sure the desired stationary vertex is the last one selected and it will scale about that point.