Private enterprises are more formal. It seems to be Saturday, Saturday, Saturday. It is not clear whether they are listed or not. There are regular holidays, annual leave, sick leave, etc. R&D departments generally only recruit experienced people, and technical departments are also good. If you just graduated from college and do sales, you usually have to practice in production for half a year, then go to after-sales exercise, and then switch to sales in about two years.
If you just graduated, try to go to a company that can get into the top 500, and go to a bigger foreign company instead of a private enterprise.