Try re-reading key points of Kurama and Naruto's relationship to better understand the dynamic between the two. If you require a rough skim of their bond look up the following chapters:
Chapter 615:
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Chapter 570:
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Chapter 569:
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It's better to understand things by yourself rather than ask. That is, unless you honestly didn't understand. I recommenced expanding your reading and not limit yourself to teenage/young-adult manga to better grasp concepts that are more difficult than this.
Seeing how the author is pretty cut and dry with their relationship it shouldn't be that hard especially given the fact that it has illustrations, something that helps children better understand. I will give you the benefit of the doubt and say you were either trolling or forgot. To have a utter lack of knowledge would mean you're just ignorant or uneducated.