Only three books 😮
1) Lefty or Joan Wulff’s book or similar on casting – maybe the FFF video by Borger – but remember – you can’t learn casting from a book any more than you can learn skeet shooting from a book. Take some lessons from a good professional instructor. My experience with FFF certified instructors has been good.
2) A good fly catalog and tying book like many of those above. I like “Trout Flies” by Dave Hughes
3) “Selective Trout” by Swisher and Richards – no other book in my opinion is a better place to start.
Welcome to the sport – it is adictive.