If my counter ends at 10 at textbox1(TB1) the random number won't show in my textbox2(TB2) - vb.net

Question

If my counter ends at 10 at textbox1 (TB1) the random number won't show in my textbox2(TB2)
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If TB1.Text = 10 Then
Dim num1 As Integer
Dim randomnumber As New Random
num1 = randomnumber.Next(100, 201)
TB2.Text = num1
End If
Timer1.Enabled = True
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
TB1.Text = TB1.Text + 1
If TB1.Text = 10 Then
Timer1.Enabled = False
End If
End Sub
End Class

Answer 1

Use a numeric variable to keep the count, not the TextBox. The TextBox.Text property is of type String, not Integer!
Putting Option Strict On at the top of your code will enforce using proper types. VB by default allows you to loosely convert between integer and string, which is poor practice.
Option Strict On
Public Class Form1
Private count As Integer
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
count = 0
Timer1.Enabled = True
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If count = 10 Then
Dim randomnumber As New Random()
Dim num1 = randomnumber.Next(100, 201)
TB2.Text = num1.ToString()
End If
Timer1.Enabled = True
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
count += 1
Timer1.Enabled = count <> 10
TB1.Text = count.ToString()
End Sub
End Class