Hi Mubin,
To clarify, are you trying to disable the footer? If so, you can create a Layout Element if you would like to disable the Footer.
Reference: https://docs.generatepress.com/article/layout-element-overview/
Otherwise, if you’re wanting to edit the Copyright in the Footer, you’ll need to activate the Copyright module in Appearance > GeneratePress: https://docs.generatepress.com/article/changing-the-copyright-message/
Hope this helps! If you’re referring to something else, kindly let us know.