Reading Business Books that Contain polytheism/kufr/shirk words

I am reading a book that is a marketing and business book. This book talks about marketing. But there are 3 to 4 sentences in this book that contain polytheism/kufr/shirk words from the spirit of Islam. The rest of the book is fine. Is it permissible to read such a book? And will the knowledge taken from such a book be halal because all the knowledge is about business?  Apart from this, I want to buy a course. And the course has about 10 parts. One part of which is the knowledge taken from this book. But the teacher does not use polytheism/kufr/shirk words in the course. Is it halal for me to take this course? Apart from this, if I buy the course and skip the part of the course taken from this book, is it okay for me? And if I can earn money by taking the course, even in a halal way, will my earnings be halal, and will I not commit shirk?