Yes. Many schools have collected sample plans for almost every lesson. There are also many teachers who have been here for a while and are familiar with most of the books to help newcomers with ideas. Schools have extra material in the form of idea books, activity resources and such but the amount depends on the size and age of the school. Some schools use a variety of textbooks, and classes are organized by English ability, not age.
Teachers are required to write out lesson plans to maintain quality, keep attendance records so that absent students are contacted, keep records of on-going assessment so parents can follow progress, and write a short class follow-up in the event a substitute teacher is required. While the schools do have strict curriculum and procedures you’ll be expected to follow, many schools also encourage teachers to bring their own teaching style and ideas to every class.