How soon can an apprentice carpenter start his career?

This can't be generalized. Depends on what you have learned. Strictly speaking, no one can start a business. Now carpentry is no longer done by one person from beginning to end as before. With the development of mechanization and intelligence, the types of carpentry are becoming more and more detailed, and the furniture made is also divided into different styles. The previous three-year apprenticeship system is no longer used in today's society, and technology, materials, equipment and so on are constantly developing and changing. Besides, carpentry is profound, even if I have been a carpenter for most of my life, what I really learned may be just a little fur. In fact, the most important thing for apprentices is to look at personal understanding. Whether they love learning or not, some people can't do a decent job independently after working with their master all their lives, and some people may be able to do it at first sight. As long as you study with an open mind, there is nothing you can't learn, only things you can't finish learning.