Dear Ansh,  you haven't mentioned the stream in which you want to pursue your Masters. However it is not mandatory that you pursue your Masters in the same stream as your Bachelor's. Based on the country you choose to pursue your Masters, you will have to appear either for GRE or TOEFL. Most foreign  Universities prefer that you have 16 years of formal education as an eligibility criteria for Masters program. Few Masters programs make it compulsory that you have practical knowledge on the subject you want to pursue your Masters in. You will need a Statement of Purpose which is important while applying for colleges abroad. You need to shortlist the Universities that have the course that you are interested in and individually check for their requirements. Each and every University has its own requirements. Also it's important to check their admission dates. You will have to start preparing atleast a year before your admission with all the paper work and documents.