You can use this user defined function:
Function redPart(x As Range) As String
Dim res As String
With x
For i = 1 To Len(.Value)
' red = RGB(255, 0, 0)
If .Characters(i, 1).Font.Color = RGB(255, 0, 0) Then
res = res & .Characters(i, 1).Text
End If
Next
End With
redPart = res
End Function
just write in cell B1
formula =redPart(A1)
and drag it down.
Result:
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