I don’t know much about lay person explanations of nuclear engineering that are accurate and accessible. I can perhaps recommend the textbooks I used in my major? Nuclear engineering is a cousin to mechanical engineering, so if you have a background in differential equations then you have all of the tools necessary to start learning the material. The physics of nuclear interactions are mostly abstracted away into tables and data, (such as the Evaluated Nuclear Data File (ENDF) which you can browse online here) so you don’t need to learn Nuclear Physics beyond the complete basics.

The introductory course at my old university, which kind of discusses general things rather than specifics, uses “Nuclear Engineering Fundamentals” by Masterson. From here if you’re specifically interested in nuclear reactors, you can study Radiation Physics (Turner’s “Atoms, Radiation, and Radiation Profection”), and then Reactor Physics (Lamarsh’s “Introduction to Nuclear Engineering” and Lewis’s “Fundamental of Nuclear Reactor Physics” and Duderstadt’s “Nuclear Reactor Analysis”). From there, if you have a background in Heat Transfer and Thermodynamics (very important) you can learn how practical (rather than abstract) reactors work using Todreas’s Nuclear Systems I. This covers mostly PWRs and BWRs. Undergrad doesn’t talk much in curriculum about other reactor types (Fluoride, Lead Eutectic, Breeders, etc) that’s mostly Graduate material.

Please note this isn’t a complete major, there’s a lot of material about radiation protection and shielding and health effects and so on.