Can you (or anyone else) recommend reading materials for me to understand 1) how state economy actually works 2) what austerity actually is and why it does/does

Can you (or anyone else) recommend reading materials for me to understand 1) how state economy actually works 2) what austerity actually is and why it does/doesn't work? As someone who was a little kid in 2008 austerity is just a mean tory boogyman that made my life more miserable and required everyone to treat people who needed social welfare subhuman but I don't really understand what the actual thinking was behind it.