IELTS Speaking is the test for non-native speakers to know how well they communicate.
The teacher is checking your fluency and natural tone during the test which you can only develop with continuous practice. Try to make small sentences or you can write ten or more sentences daily about what you did in your classroom or at your work etc.
When you are in the process of thinking in English, you are then in the whole world of a different language. Stand in front of the mirror and talk, try to explain it more and more. Also write on the same topic, think carefully and try to find synonyms. Do this exercise daily which will overcome your hesitation.
Well I can help to begin, okay lets talk about weather. How was the weather today?