While there's an implied question here, the link has plenty of adequate responses.
If you want to learn Lisp, I recommend Common Lisp, or else a Scheme implementation with lots of practical extensions (e.g. Chicken or PLT). _Land of Lisp_ is a good intro. _SICP_ is also excellent, but hell-bent on teaching you long-term deep theoretical wisdom rather than useful-today tricks. But either way: Do the exercises. Try writing your daily experimental code in it. Think in it. Make it work. Live in it.
If you want to learn Lisp, I recommend Common Lisp, or else a Scheme implementation with lots of practical extensions (e.g. Chicken or PLT). _Land of Lisp_ is a good intro. _SICP_ is also excellent, but hell-bent on teaching you long-term deep theoretical wisdom rather than useful-today tricks. But either way: Do the exercises. Try writing your daily experimental code in it. Think in it. Make it work. Live in it.