(A)
United States universities need TOEFL or IELTS test scores to enroll to the university. Most students get overwhelmed and stressed while they are preparing for those tests.
I personally studied from YouTube since many teachers who have been teaching English for a long period of time make videos on how to prepare for the test. They provide helpful methods and ways to answer those difficult questions with some easy steps on their videos. I also used Long-man's TOEFL preparation book, which was quiet helpful. My only advice that I would give is always use methods while answering because it makes all the questions seem easy.
(B)
In Saudi Arabia you need to get high score in some tests so you can enter university. There are two type of tests in Saudi Arabia, The first type is called "Qudurat", this test measures your ability to analyze questions and how your education basics are. The test has two parts, the first part is math and the second part is Arabic. the average score most students get is 65-70% while the score most universities need is 80% and above.
The second test is called "Tahseli" which is taken after the student graduates from highschool. This test measures your knowledge background and basics since you started highschool. For alot of students this test is more difficult than the Qudurat test because it has Math, Biology, Physics, Chemistry, and English. To study those two test you need to study for a long time. People spend alot of money buying preparation books and registering for preparation courses since those two test determain their future.