1. General limited liability companies and joint stock limited companies have the position of chairman. You don't have to be a listed company like a company limited by shares.
2. The chairman is generally elected by the board of directors; The board of directors is elected by the shareholders' meeting of the company. If a small company does not have a board of directors, it shall be elected by the shareholders' meeting or according to the articles of association.
The chairman has the highest status, that is, the boss. The general manager is a senior part-time job. An inappropriate metaphor: just like an emperor and a prime minister.
If it is a one-person company, you can call yourself the boss or the executive director. Others don't know what an executive director is, so they say they are the boss. If it is a partnership, it is strictly problematic to call the general manager and chairman because the company cannot be registered. Of course, in order to facilitate external contacts, partners can also negotiate to determine who is the chairman and who is the general manager. It's just not the same as the legal meaning.
Knowing so little, there must be some imperfections. I hope the above answers can help you.