Suggest a book (fiction or non fiction) which will help me regain my belief in myself, boost my image in my own eyes and help me get better to not feel like I’m a fraction of the person I was mentally.

Just as the title says. Life has beaten me down for since past few years and I’m at the lowest point in my life. Want to grow out of this and feel like I can regain my spark again, my will power again and my self confidence again. Please be kind and recommend, thank you. 🙂