Im 26 male,5.6' height.im very thin in all aspects such my arm muscles is 11inch,thigh 19inch waist 32inch.?

i want to add some weight and width to my body. so tell some of the measure to do so,and also precaution for eating habits.some i feel lyk im very short and thin.im very sad because of this,my girlfriend also want to leave me as she feel insecure with me.please tell what to do.and inside me i also feel that i have no confidence.you give me diet chart or recommend some exercise for different bodyparts as for arms, leg, waist ( also my face very small ) please help me.plz give some good suggestions.