For chest muscle training, it is best to do several groups of push-ups with wide grip at the beginning, such as 3-5 groups, each group10-20; Two or three groups of birds, each group 10- 15 is more reasonable.
In addition, it is not good to exercise chest muscles and the effect is not good. It is best to have three groups of dumbbells on your shoulders, each group10-15; Leg squat in 3-5 groups, each group 10-20, can promote body shape and muscle growth; 3-5 groups of back pull-ups, 5- 15 each, some abdominal muscle training will be more perfect.
My very best wishes to your health