Public Class Form1
    Dim num1 As Integer
    Dim num2 As Integer
    Dim Answer1 As Integer


    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
        num1 = textBox1.Text
        num2 = textBox2.Text
        Answer1 = num1 + num2
        lblAnswer1.Text = Answer1

    End Sub

    Private Sub Label_MouseHover(sender As Object, e As EventArgs) Handles Label1.MouseHover
        Label1.Text = "Enter a number in text box"

    End Sub
    Private Sub Label1_MouseLeave(sender As Object, e As EventArgs) Handles Label1.MouseLeave
        Label1.Text = "Label1"

    End Sub

    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
        Label1.Text = "Enter a number in text box"
    End Sub
End Class