I have this book, and I think it will entertain you and keep you interested. George R. R.Martin used it to help flesh out his Game Of Thrones series!
https://www.amazon.com/Life-Medieval-Castle-P-S-Paperback/dp/0062414798
Cool!
“what day-to-day life was actually like during the era,”
That sounds perfect, and even better that it is a series!