So the way this works is:
Range("V2").Select
Range(Selection, Selection.End(xlDown)).Select
As though you were doing it manually, this is saying that the range to be conditionally formatted will span from V2 down to the last row in that column.
Selection.FormatConditions.Add Type:=xlExpression, Formula1:="=V2=P2"
It then applies the formula
to each cell in the selection, so this addresses your question re: how to define I. In terms of colour, you can use the RGB function here
.Color = RGB(255,100,100)
Hope that helps.
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