2, arm flexion and extension: two chairs can be used instead at home.
3. bench press dumbbells. Weight depends on your own situation, a group of 8- 12 4 groups. If possible, you can do an upward oblique push, mainly to the upper part of the pectoral muscle. Combined with flat bench press, each movement has 3 groups.
4, pull-ups, can be carried out on the door frame at home. A group 12- 14, 6 groups. You may not be able to pull it up at first, but as long as you stick to it, you can do it after your strength is enhanced.