Online English classes are available in a number of price ranges. There are free English courses that offer a certificate of completion for $50 to $99. You could opt to take an English course that specifically helps you with your business goals. A Business English Course could cost as much as $356 for a 4 course, 4-6 week program.
Your needs may be simple. You may simply want to speak English conversationally. These types of courses are available as are courses, which focus on reading and writing English. Most online learning resources offer a certificate verifying your completion of the course.
Research the online resource thoroughly. You may find that the course is being taught by an accredited University. This fact would further legitimize any certificate you receive for completing the course. This proof could prove valuable when seeking employment with an employer who needs English speaking, reading and writing employees.