Roman Polytheism Reading Recommendation: An Introduction to Roman Religion
An Introduction to Roman Religion by John Scheid (translated from French by Janet Lloyd) is a decently short little book introducing (as the title suggests) some basics about the historical practice of Roman polytheism. It goes over important topics such as the fundamental differences between it and other religions, religious rituals and spaces and the figures involved.
I believe this book can be a really good entry point for those interested in Roman polytheism. It is quite short and relatively easy to read, though some parts can be a little dry if you're not as interested in them. It also lacks a deeper discussion of the Gods themselves and instead strongly focuses on the religious structures of Ancient Rome (so if you're looking for that particular information, this is not the book for you). I would suggest that this book not be your only source, but one of many that can help strengthen your general understanding of the historical context. The Further reading section of the book can be a good start for finding more reading materials.
A digital version of the book is available to read on the Internet Archive (login may be needed first). ᵈᵐ ᵐᵉ ᶠᵒʳ ᵖᵈᶠ