hi mail25,
Go to theme folder > haeader.php and you will see do_action( 'attitude_before' );
code on line no 53. You can add your code just before this line to display your code in header and the added code will be displayed in every page of your website.
We recommended you not to change the code. If you need to customize the code then we recommended you to create a child theme and use this hook do_action( 'attitude_before' );
and add your action into your functions.php of child theme. So that while updating to new version your customized code will not be lost.
Otherwise each and every time while updating to new version same code customization is required in header.php
Thank you!