Here is the list of search terms I came up with for my research process:
-American Universities International Admission
-International admissions rate
-The acceptance rate at universities
-English proficiency exam
-Transfer students
-American Universities admission requirements
-Financial requirements for international students
-English proficiency test
And I found a source for my essay that I think could be very helpful. It is a website called TheSpikeLab, I think it is relevant because they conduct a lot of information and data before providing their articles to the audience. Also, the provided information is based exclusively on statistical analysis and facts.