If you are struggling with RPG creation in Unity, this book should help. It includes 432 pages that painlessly take you through all the necessary steps to create your 3D RPG in Unity including a dialogue system, an inventory, a shop system, real-time combat, randomly-generated procedural levels, a quest system, along with intelligent NPCs. Along the way, you will also learn how to create systems that you can reuse in other games and that will speed up the development process.
Unity from Zero to Proficiency (Proficient) is available today on Amazon for $3.99 (promotional offer until Friday).
Hope this helps
https://www.amazon.com/dp/B07Z45N6J1