@xayah297 wrote:
When trying to draw on top of cad drawings. Revit selects endpoint of the lines and not the centre between them to create Walls. I saw a video where a guy drew directly on top of these lines from the centre between them.
I think what you are seeing in that video is a guy tracing a wall using a specific Wall Location Line. If he was tracing on the outside, as you are, then I suspect his Wall was using Finish Face: Exterior.
The wall’s Location Line specifies which of its vertical planes is used to position the wall in relation to the tracing path.
https://knowledge.autodesk.com/support/revit/learn-explore/caas/CloudHelp/cloudhelp/2019/ENU/Revit-M...
...If you are actually tracing an exterior Wall to an interior partition Wall, then trace on the interior side using Finish Face: Interior.