if you have a class MyForm : System.Windows.Forms.Form (which you create using the Windows Form Designer)
You can do
MyForm form = new MyForm(); form.Show();
Launch an instance of MyForm.
However, if you want to create a simple confirmation or message dialog box, check out the many uses for MessageBox
MessageBox.Show("text"); MessageBox.Show("text", "title", MessageBoxButtons.OKCancel);
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