When using Royal Mail OBA through Shiptheory, you're able to send with a variety of services, provided they're enabled in your OBA account. You can see the full list here.
Royal Mail Tracked services are some of these. In the past, you may have had to include tracking stickers on your orders going with these services, but that is not the case when using Shiptheory. You'll only need the label printed from Shiptheory.
After booking in a Tracked service with Shiptheory, it will be added to your day's manifest, and once you've hit "print manifest" in Shiptheory, the electronic data for the order will be sent to Royal Mail.
Once this has happened, you will be able to track the order on the Royal Mail system itself. You can do so by clicking "Track" on the order in Shiptheory:
Alternatively, you can access the Royal Mail Track and Trace page directly and type in the given tracking number for the order: https://www3.royalmail.com/track-your-item#/
If you have any issues or any questions, please feel free to contact support.