I have done BA LLB and I don't want to become a lawyer but I am interested in business. Should I do CS or MBA?

Both are good options. CS is also good option. In CS, you are going to study all about company law that will help you as you have studied LL.B. And after doing CS, you are not going to work with and lawyer or you are going to be a lawyer. You are going to work in a company as advisory of company. Or

You should go for MBA. You have many fields that you can choose. You will be given a year to choose your field of specialisation.