As already said before, that is not possible. What you can do is create a dictionary of Func(Of T) and then invoke those by passing in your operator:
Sub Main
Dim operations As New Dictionary(Of String, Func(Of Double, Double, Double))()
'Set up operations for addition, subtractions, multipication, and division
operations.Add("+", Function(l, r) l + r)
operations.Add("-", Function(l, r) l - r)
operations.Add("*", Function(l, r) l * r)
operations.Add("/", Function(l, r) l / r)
Dim result As Double = operations("+")(5, 5)
Dim result2 As Double = operations("*")(5, 5)
Console.WriteLine(result)
Console.WriteLine(result2)
End Sub
DoMath(1, 2)