Use the LinkLabel
as you would be using a button, by executing code in the click event. Open the form (or bring it to the front if it is alreay open) programmatically when the user clicks the label. You will not be able to set an URL to a form.
private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{
Form2 form2 = Application.OpenForms.OfType<Form2>().FirstOrDefault();
if (form2 == null) {
form2 = new Form2();
form2.Show();
} else {
form2.BringToFront();
}
}