If you only work part-time for a while, there is no need for special training.
First of all, the training fee is a sum of money, and secondly, it will take up a lot of your time.
At present, the touring coaches in the gym are all half a bottle of water, and the professional coaches are not at their charging level at all. Read more books on this subject by yourself, and then look for more information on the Internet to popularize the basic knowledge.
It is impossible for a gym to hire a private trainer or a woman to lose weight. Knowing these aspects can teach beginners.