make for someone만들어 주다 means to make something for someone or do something that benefits them. The form 만들어 줄 is commonly followed by an ending such as 게, 거야, or 거예요.
KO: 내일 아침에 맛있는 샌드위치를 만들어 줄게.
EN: I'll make you a delicious sandwich tomorrow morning.