C#

private Point mousePos;
private Point panelPos;
private bool isDragging;

private void panel1_MouseDown(object sender, MouseEventArgs e)
{
    if(e.Button == MouseButtons.Left)
    {
        isDragging = true;
        Cursor.Current = Cursors.Hand;
        mousePos = panel1.PointToScreen(e.Location);
        panelPos = panel1.Location;
    }
    
}

private void panel1_MouseUp(object sender, MouseEventArgs e)
{
     if(isDragging)
    {
        isDragging = false;
        Cursor.Current = Cursors.Default;
    }
}

private void panel1_MouseMove(object sender, MouseEventArgs e)
{
    if (!isDragging) return;
    Point point = panel1.PointToScreen(e.Location);
    panel1.Left = panelPos.X + point.X - mousePos.X;
    panel1.Top = panelPos.Y + point.Y - mousePos.Y;
}