How to edit footer

At first go to theme directory find inc>functions.php then search for “colormag_footer_copyright” edit this code bellow as you need:

add_action( 'colormag_footer_copyright', 'colormag_footer_copyright', 10 );
/**
 * function to show the footer info, copyright information
 */
if ( ! function_exists( 'colormag_footer_copyright' ) ) :
function colormag_footer_copyright() {
   $site_link = '<a href="' . esc_url( home_url( "https://wordpress.stackexchange.com/" ) ) . '" title="' . esc_attr( get_bloginfo( 'name', 'display' ) ) . '" ><span>' . get_bloginfo( 'name', 'display' ) . '</span></a>';

   $wp_link = '<a href="https://wordpress.org" target="_blank" title="' . esc_attr__( 'WordPress', 'colormag' ) . '"><span>' . __( 'WordPress', 'colormag' ) . '</span></a>';

   $tg_link =  '<a href="https://themegrill.com/themes/colormag" target="_blank" title="'.esc_attr__( 'ThemeGrill', 'colormag' ).'" rel="designer"><span>'.__( 'ThemeGrill', 'colormag') .'</span></a>';

   $default_footer_value = sprintf( __( 'Copyright &copy; %1$s %2$s. All rights reserved.', 'colormag' ), date( 'Y' ), $site_link ).'<br>'.sprintf( __( 'Theme: %1$s by %2$s.', 'colormag' ), 'ColorMag', $tg_link ).' '.sprintf( __( 'Powered by %s.', 'colormag' ), $wp_link );

   $colormag_footer_copyright="<div class="copyright">".$default_footer_value.'</div>';
   echo $colormag_footer_copyright;
}
endif;