It is important to learn business English if you are going to be successful in another country where English is the primary language. It will also be a great idea to practice speaking and writing in business English. If a university offers a course on business English, it will be a good idea to take the class. Reading, writing and speaking English is necessary to start a business. Business English is different from asking where to find the nearest hotel. There are classes you can take to help you but there are things that you can learn on your own. Vocabulary and grammar are a good place to start with. You need to know what words mean. Later, try to pronounce the words and then look them up in the dictionary. Try using them in a sentence and ask someone who is good at English to help you. Once you have an understanding of English, you can use it in business English. In business you will have to learn such things as taking messages, answering the phones with proper words and communicating with your co-workers. You may have to learn how to make travel plans. Business English is very different than spoken English. Grammar is the same but you have to learn things like expressing yourself in a proper manner or maybe making a report in your office. If you are working in the customer service sector  , you really have to learn business English. Dealing with the public is sometimes more important than asking your boss for a raise  . Most businesses offer training classes and some companies offer classes on how to do the job with proper business English. Why do people learn business English?
They want successful communication. They want to ask the boss for a raise. They want to have their own company. They will have a chance to get a better job.