So I suggest you don't do a lot of weight training. If you want to make yourself stronger, you'd better do unarmed exercises now, such as push-ups, sit-ups, parallel bars arm flexion and extension, pull-ups, squats, vertical jumps and so on. As long as you persist, you will also receive satisfactory results. At the same time, doing more aerobic exercise, such as running, basketball and swimming, is very good for your health.
Gyms are 50-500 yuan per month, and gyms in schools or communities are generally around 300-500 yuan.