I would love to recommend a book - " How To Win Friends and Influence People " DALE CARNEGIE.
I really like to read classic items that have "created" what we call personal development in the US and Europe today. Carnegie is the oldest, most durable foundation of this category. More decades were built on his shoulders: Hill, Schwarz, Ziglar, Robbins. Even today's cleavage can lead to its primary inspiration with a little effort.
Carnegie's style is jovial, simple, very chatty. It's wonderful to read, preferably only 2 or 3 stories at a time, not to overdo it. A lot of things have already changed in the world, but the meaning of his anecdotes is timeless.