You can target specific pages using Google Ad Manager’s key-value targeting. Key-values helps you to target specific pages or ads slots in the pages (ATF, BTF, etc.), URLs, or ad inventories.
Typically, you have to create key-values and use it in the line item targeting and ad tag. On a higher level, this is how key-value targeting works:
1. Define keys and values in Ad Manager.
2. Add key-value targeting to your Ad Manager line items.
3. Add key-values into your Ad Manager ad requests. You can do so by editing the ad tags included on the page. For adding key values to specific ad slots, you can use the syntax “.setTargeting(‘Key’, [‘Value’])” and for adding KVs to specific pages, you can use “googletag.pubads().setTargeting(‘Key’, [‘Value’])” as syntax. For detailed implementation, refer this page.