Equipment you need: a bench and a pair of dumbbells (22-30k g/ piece, detachable, of course, because different movements require different weights). With dumbbells, you can bench press and fly (practice chest); Can stand upright, cross-lift, front cross-lift (shoulder training); Can do all kinds of arm bending and lifting (biceps brachii); The dumbbell behind the neck bends and bends the arm support (triceps brachii), and you can also do squats and weight-bearing lunges (leg training); You can also do dumbbell bending and rowing (latissimus dorsi). This will build most of your muscles (though not as good as in the gym). Detailed action decomposition, you'd better check the information, a lot.
As for the training plan, you can practice one part (chest, back, shoulders, arms, waist and abdomen, legs) every day, and each part has no less than 20 groups of movements, each group is 8- 12. These 20 groups can be one or two movements, and you can see which movement stimulates your muscles the most.
As for the weight, it is the maximum weight you can bear on the premise of ensuring accurate movements. It is meaningless to say numbers, and it is impossible for others to know your strength. And different movements also need different weights. This needs to be tried by yourself, starting with a light one.
Just start practicing, be careful not to be too intense, just once 1 to 1 half an hour. Take a day off every two or three days of training (depending on your physical condition).
In fact, the best choice is to go to the gym, if you 17 or more, if you have time.
As for diet, eat more things rich in animal protein, beef, milk, chicken and egg white are all good, and whey protein can be considered after half a year. Eat more fruits and vegetables. Usually you can eat five meals a day (or add some milk, bread and other energy between meals).
That's all I can think of. I hope it helps you.