Every countries institution has their own criterion for international students to be admitted in their institutions. All educational institutions require academic background of student plus they see English proficiency of student as well. For English assessment institution demands for TOEFL/IELTS/CAE/PTE results. SAT/GMAT/GRE is also the requirement for few countries as per student education level.
These things are not commonly known by students so we have to make them clear about these requirements.