Hello, you did not inform the text to which this question refers, which makes it impossible for it to be answered accurately and satisfactorily, but I will try to help you in the best possible way.
The central statement of a text, refers to the position of the author in relation to something or refers to the very theme that the text decides to address. This central statement is established through arguments that spread throughout the text and that are supported by supporting details that value, justify and prove that the arguments are correct. This is because these supporting details show real evidence, which justifies the establishment of the arguments that, in turn, justify the establishment of the central theme. Thus, to answer your question, you must look for the position of the author in the discourse and thus find how that position grows, based on the evidence presented.
