The Mountain is You by Brianna Wiest is a guide to stop self-sabotage and build the life you want. It shows how to change emotional habits blocking growth, let go of the past, imagine your future self, and separate good intuition from bad intrusive thoughts.
The Power of Now is about living in the present moment so you suffer less and have more inner peace. It's really about reconnecting to your physical senses rather than being lost in thinking. Eckhart Tolle says past and future are only mental simulations because your life always happens Now.