This book is fantastic for a number of reasons, but what I think it does more than anything else is provide a very strong argument for taking a sincere interest in people other than yourself. Carnegie does a great job highlighting a number of micro-skills that lead to success, whether it be in business or relationships.
Best advice here, that often shows up in quote form – if you want to be perceived as being interesting, be interested.
Farnam Street has an excellent, brief summary – doesn’t go into a ton of detail but if you’ve only got two minutes and want to get a feel for what the book is about, check here:
https://fs.blog/2012/07/how-to-win-friends-and-influence-people/
Why reinvent the wheel, right?