The purpose
Select a mesh based on its structure from an object created from multiple meshes (e.g., by joining objects or adding them in Edit Mode).
For example, I want to select only one object from an object composed of two overlapping spheres.

Environment
Blender:3.4.1
OS:Windows 11
Select with link
Select a portion of the target mesh
Switch to Edit Mode and select a clearly identifiable part of the target mesh (a vertex, edge, or face).

select areas where the two meshes do not overlap.
Selection of vertices linked to the selected location
This selects the vertices linked to the selected location. We will introduce two methods; the results are the same.
From menu
Select “Selection” from the top-left menu, then select “Link Selection,” and finally select “Link.”

Shortcut
Press L key.
Shortcuts may not respond after switching windows, etc.
You need to re-select and re-enter the keystrokes.
Result
We are able to select only one object from the overlapping pair of spheres.

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