I definitely recommend books by Thich Nhat Hahn and Wayne Dyer. “The Miracle of Mindfulness” https://a.co/d/5mVoTmW is a great one by the former.
“Happiness is the Way” by Wayne Dyer is one I’d highly recommend starting with, as well. https://www.hayhouse.com/happiness-is-the-way-hardcover
I also recommend meditating regularly and journaling regularly, as well. These practices will help you learn more about yourself and feel more connected spiritually.