The main training method of abdominal muscles is sit-ups. After proficiency, you can do weight training. Back muscles can do reverse sit-ups and weight training.
Deltoid muscle is easy to see in arm muscles, so it is recommended to train deltoid muscle more. The training method is to hold weights such as dumbbells and do flat lifting exercises repeatedly (the arms naturally droop until the arms are flat).
No matter where you practice muscles, it is important to keep training every day and gradually increase the intensity of training.
In addition, I think the landlord may want to be in good shape. I suggest you learn to dance, and dance more vigorously, which will help shape your figure.