At the beginning of exercise, you can do the whole body muscle group training (such as chest, shoulders, back and legs), and each muscle group can choose an action, with 4-6 groups of each action, 8- 12 times in each group (8- 12 times after exhaustion), and train three times a week.

1-2 months later, differentiation training (such as upper body and lower body separately, trunk and limbs separately), each muscle group selects 2 movements, each movement is 4-6 groups, each group is 8- 12 times, 4 times a week (every two full-body exercises 1-2 days).

After 3-4 months, carry out targeted training. Train large muscle groups with small muscle groups every time (for example, chest muscle plus triceps, latissimus dorsi plus biceps brachii, thigh muscle group plus waist and abdomen training, and make reasonable arrangements according to your own situation). Choose 3-4 actions in each cluster, 4 groups for each action, and 8- 12 times for each group.

Maybe it's because your weight and number of groups are not properly arranged. What I said above is only a high probability. You can look for the specific training movements of each muscle group. If you can exercise as seriously as I told you (it is recommended to go to the gym more after exercise and eat more high-protein foods, such as eating one egg white and one egg yolk less every day), I think you will find that your muscles have increased a lot in half a year! Ha ha! Wish you success!