I am a CTO today (albeit for a small startup right now), but I have run teams of 120+ people and I have run my own successful businesses. So my advice comes from that knowledge and experience growing an engineering team from 6 to 120+ in a year.

Books are interesting to read and can give you ideas, but in the end it is leadership that solves the problems and makes teams successful, not which OKRs you put in place. In fact, OKR's can be the death of a team if they are done incorrectly, and just cause Google uses them doesn't make them good. Six Sigma was invented at Motorola who used it mainly properly, GE started with it in a good way then twisted it so badly that it became a problem not a solution. Sadly that trend went around multiple industries, much like OKR's today. That's just an example though. OKR's and six sigma can be used properly to great success, but be careful with trends when you are a leader.

To the things you asked about specifically, there is no book or set of books I know of that will answer it all. Most of being a good CTO isn't about the technical part of the job or engineering specifically, it is about people. So if you are not a good people person that is the place to start. Read about people, read psychology books, read sociology books, understand how group think works and how to avoid it etc. Make sure your life is in order so you are not running around like a chicken without its head, because how you work is how your team will work. So if you are a negative person you'll surround yourself with negative people, either because you hire them that way or you'll make them negative through your own behavior. Negativity is bad, fairly blunt honesty with positive reinforcement is good.

Growing a team from 0-8 vs from 10-30 isn't much more difficult, the rules stay the same but you have to setup more structure. The biggest mistake new CTO's and Founders make is they don't put in organizational structure, thinking a flat organization is ideal, and truly flat. Flat organizations are great, but it does NOT mean you lack structure, please read on this if you don't understand it. People need to know who to go to when, how to resolve an HR problem vs an engineering issue etc. 90% of the time I see growing teams in trouble it is from a lack of organizational structure and process. And process doesn't mean some heavy weight manual on how to do a job, just where to go for what and when and who to ask what types of questions for quick resolution.

I could go on and on about each of the issues. What you need is a good mentor to help you and to give you advice. My 2 cents, if you want to grow with the organization into a technical leader understand that you need to be a people person and your technical ability is second. IMO you should never lose your technical knowledge and I feel CTO's should always remain highly technical ( at least in knowledge ), but your primary job goes from technology to leadership, so if you are touching code in a company that size as CTO you have failed big time. If you want to touch code, move to the principle or staff engineer type position and not a CTO/VP etc.

As for books:

Crossing the chasm (get the latest edition) -- good for technical product introductions and marketing behavior. CTO's/VP's etc need to know marketing and business methodologies well to be successful.

The Essential Drucker -- not saying I agree with everything, but at least it helps you understand a lot of concepts and you can see patterns.

Chainsaw by John A Byrne -- This book is about Al Dunlap and Sunbeam and corporate greed. I think all new founders, managers and business people should read it. It isn't a guide to being good but showing how you can destroy a company quickly. So worth the read, and interesting characters.

Also read all kinds of management books and military leadership books for special forces etc. It gives you good information on how to create high performance loyal teams.