창업하다 is normally used for starting new business 회사를 창업하다 this word is from traditional Chinese word. 차리다 is pure Korean about starting the new business but it’s used for small scope. Like 가게를 차리다 식당을 차리다 열다 is just for action to open something 문을 열다 If you say 가게를 열다 : it’s for open the restaurant but it doesn’t mean starting the new restaurant, it means open to welcome the customers that day. 세우다 means “ build” in English. You can say 빌딩을 세우다 means build the building 시작하다 means “start to do sth” or “ begin to do sth” in English. It’s like you cause the thing happens. 한국어 공부를 시작하다( start to learn Korean) 일을 시작하다( start to work) 짖기 시작하다(start to bark) 다시 시작하다(start again)