We are sorry for misleading but instruction is quite similar.
yes go to the directory wp-content/themes/mags-pro/inc/mags-widgets.php and go to line no: 1259, 1262 and 1265. there you can see the ‘Popular’, Recent’ and ‘Commented’ text as <?php esc_html_e(‘Popular’,’mags’);?> just replace the text ‘Popular’ as your need and change other two as same.
We recommended you to edit those code by creating a child theme so that your code won’t be lost while updating the theme to the new version.
Thanks