What is the basic eligibility criteria which one needs to meet to qualify for admission in an American university/college/institution

The basic eligibility criteria for seeking admission to a university/college/institution in the USA are:-

Bachelors

• Successful completion of international education equivalent to US secondary education (12 years)
• School mark sheets demonstrating completion of senior secondary education in the native nation
• Proven academic achievements demonstrating the ability to succeed in university level studies
• English Proficiency Test Scores.

Master’s degree 

• International Bachelor’s degree equivalent to an American four-year Bachelor's degree, from an accredited university
• In case you have a three-year Bachelor's degree or diploma, you can complete a qualifying Pre-Master's program first
• English Proficiency Test Scores (may vary from university to university).
• Official documents for all colleges/universities attended
• Two letters of recommendation

Doctorate Courses

• Relevant Bachelor’s and Master’s degree from a recognized university
• English Proficiency Test Scores.
• Work experience (as mentioned on the site of the university)