To run code from both main function and class event - vb.net

Question

I'm calling a form from my main function, this form has a button on it; this form is defined inside its own class. My goal is that every time I click that button, the program will perform a task defined in the "click" event, but it will also perform a task in the main function at the moment of clicking that button.
I tried switching between oForm.Show(), but the main function runs the code before even starting the form. I also used oForm.Show(vbModeless), but this causes the opposite: the code in the main function runs after the form was closed.
This is my code:
Imports System.Windows.Forms
Public Sub Main()
Dim oForm As New WinForm()
oForm.Show(vbModeless)
' I want to show this when I click the button
MsgBox("TASK 2")
End Sub
Public Class WinForm
Inherits System.Windows.Forms.Form
Public Sub New()
oForm = Me
With oForm
.FormBorderStyle = FormBorderStyle.FixedToolWindow
.StartPosition = FormStartPosition.CenterScreen
.Width = 300
.Height = 400
.Text = "MYFORM"
.ShowInTaskbar = False
End With
Dim oButton1 As New Button()
With oButton1
.Text = "CLICK ME!"
.Top = oForm.Bottom - 80
.Left = (oForm.Width/2) - oButton1.Width
.Enabled = True
.AutoSize = True
End With
Me.Controls.Add(oButton1)
AddHandler oButton1.Click, AddressOf oButton1_Click
End Sub
Public Sub oButton1_Click(ByVal oSender As System.Object, ByVal oEventArgs As System.EventArgs)
MsgBox("TASK 1")
End Sub
End Class
How can I achieve this?
Thanks in advance