How unity handles work?

Scripting
1

OK I added DotHandleCap to each mesh vertex.
Now I would like to select some of these Handles change their color, and use their position to determinate which vertaxes in vertax list i have selected.
The PROBLEM is, I have no idea how these handles can be seleced and how to put the in the list

for (int i = 0; i < DV.VertTransformArray.Length; i++) {
            Handles.DotHandleCap (i, DV.VertTransformArray [i], DV.transform.rotation, 0.1f, EventType.Repaint);
    
        }

This code adds DotHandleCaps to vertexes, but what does EventType.Repaint Does?
How can I make funciotn if( dothandle is pressed change collor, take its ide and put it in the list?)

2

Looks like you want to use a free move handle

and

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