The Money Makeover by Dave Ramsey.

In my mid twenties, this book helped me pay off all my student loans and build an emergency fund with 4-6 months of runway. It changed the way I think about money.

I Will Teach You To Be Rich by Ramit Sethi.

This built on top of Dave Ramsey’s by helping me create a system to build my wealth through investing and still continue to save towards future goals/emergencies.