I recommend New Oriental, Zhonggong Education and Qihang Education, all of which are top training institutions in China.
There are many recruitment and counseling agencies. If you want to enroll in a training class, it is suggested to consider the following aspects:
Whether it is formal or not, if you want to choose a big company, don't choose a small organization that a few people improvise. There is no guarantee.
Working hours, which indicates whether it is professional or not.
Economic strength, this is the guarantee.
The teaching environment directly affects the learning effect.
Whether there are professional teachers and R&D teams.