When applying for undergraduate admissions abroad, prospective students are typically required to submit a set of essential documents namely academic transcripts from their high school or secondary school, standardized test scores like the SAT or ACT, and proof of English language proficiency through exams like TOEFL or IELTS, especially if English is not their native language. 

Additionally, letters of recommendation from teachers or counselors, a statement of purpose or personal essay explaining their academic and career goals, and a detailed resume or CV highlighting extracurricular activities and achievements are commonly requested.  

For certain programs like art or design, applicants may need to submit portfolios showcasing their work. Moreover, applicants must pay the application fee, which varies by institution. 

It's important for prospective international students to closely follow the application guidelines and deadlines provided by the specific universities or colleges they are interested in. Meeting these requirements and ensuring that all documents are prepared and submitted on time is crucial.