Course in a language school
Preparation for Cambridge English exams should only be given by qualified teachers with experience. A quality school will be able to provide you with all the information you need for the Cambridge English exams. To be eligible for the course, it is ideal to take an entrance test and an interview to find out what timeframe is realistic for you to pass the exam.
In the region of Brno and its surroundings we recommend you for preparatory courses Jazyková škola P.A.R.K. 
https://www.skolapark.cz/
In the region of Prague and its surroundings we recommend Jazyková škola Zpěváček 
https://www.jazykovka.info/