Shopify app - need basic app that fire our tag on all pages and on thank you page

need to build addon/module/plugin for SHOPIFY eCommerce Our clients need to add JS Tag to them platform. on all site pages and another TAG on the thankyou page. We need to build simple module that will fire our JS custom tag! but the user only will need to add the most basic module ;) our users need to add JS tag to the eCommerce, we want them to have simple life , and they will use the app, and will add in the app only the USER ID XXXX + YYYY. based on the user ID we will fire the right tag. EXAMPLE: ALL PAGES TAG: <script> (function(){var e=[login to view URL]('script'); e.async=true; e.type='text/javascript'; [login to view URL] = [login to view URL] + "//[login to view URL]"; var me = [login to view URL]('script')[0];[login to view URL](e, me);})(); </script> THANK YOU PAGE TAG: <img style="display:none;" src="//[login to view URL]" /> User will have only one screen to add the XXXX and the YYYY nunbers we provide him Well who is the faster master???