Set function keys to button click

I need to set f2 key to button on my winform

  private void UserPopUp_KeyPress(object sender, KeyPressEventArgs e)
        {
            if(e.KeyChar == (char)Keys.Enter)
            {
                button3.PerformClick();
            }
            if (e.KeyChar == (char)Keys.F1)
            {
                MessageBox.Show("hi");
                uaddbtn.PerformClick();
            }
            if (e.KeyChar == (char)Keys.F3)
            {
                button1.PerformClick();
            }
            if (e.KeyChar == (char)Keys.Escape)
            {
                MessageBox.Show("hi");
            }
        }


but here f1 and f3 buttons are not working.Enter and escape is working

please help to set these f1 and f3 keys to perform above actions