There are 2 main paths for entering the U.S. labor market once you graduate from your course of study and have the right to work in the U.S.:
Many large employers offer internship programs that allow you to gain experience through intensive training and development. You may also receive extra funding from your employer for additional professional training.
It's becoming more and more common that graduates find employment that is unrelated to their degree subject. What's important to employers is that you can learn and apply your skills to the job. These training programs can involve a lot of extra study outside normal working hours and may also include demanding professional exams. If professional qualifications are not necessary, the training is less likely to involve academic elements.
Many jobs require the specialist knowledge you gained through your studies. When you apply for a job that is not part of any graduate training program and uses the knowledge you gained during your studies, we refer to that as direct entry. Some on-the-job training may be required and may involve steps to allow you to qualify to be registered with a professional body. An increasing amount of graduates are finding positions in small and medium-sized enterprises (SMEs), where the direct entry method is commonly used.
Many factors are involved when it comes to employer attitudes towards international students, so it is not recommended to generalize them.
Applying for a work visa for a new employee is a time consuming and expensive process, so you can understand why they only want to go through that process for outstanding candidates who have special knowledge or talent to offer. If you do not need a work visa, you should make that clear in your initial contact with the company by including that information in your cover letter.
Employers who have a presence in your home country may be interested in employing you during your 12 months of OPT here in the US, sending you back home for at least a year, and then bringing you back to the U.S. on an Intra-company Transfer Visa, or L1 visa.