A char variable represents a single character, such as a single letter or symbol. It cannot be used for a string such as "Kevin" ... Have you learned about arrays yet? Generally a string is represented as an array of characters. I'm not sure which textbook you're using, but it may provide you with its own String class for you to use. If you do a #include or "String.h" or some variant at the top of your program, you should be able to have a String kevin; The thing is, that for some reason, strings aren't natively built-into the C++ language and need to somehow be worked in.
In addition to that, a string should always be referenced by double quotes while a character by single quotes. Therefore, once you get the string declaration worked out, it should read if (x == "Kevin") ... Good luck! :)