Books to become courageous

Hi. I feel I really lack courage in my life. I'm always scared and anxious to get in certain situations in life, overthinking a lot. I feel this is destroying a lot of possibilies in my life. I feel like Marty McFly's dad in back to the future. I'm a chicken.

Is there a book that could help me build fortitude of character? I wish I could be a brave warrior like Achilles: fearless, brave, heroic. I want to be something similar in real life. Stubborn, obstinate, not giving up when things get hard. I'm the opposite right now. I always give up and complain how difficult things are. I'm really weak mentally.

Which books can I read to become braver? I know I won't become automatically braver by reading books. I need to put in the work in real life but I feel I need a guide. A manual. An inspiration. Thank you.