svar is being used in a lot of exciting, incorrect ways. It's a single char, but you pass its address to scanf when it's expecting to read a string. This will smash memory. You then pass the value of svar to stringWithCString:encoding: which expects an address, specifically a char *. This will likely cause a crash. You then assign the result of a method that returns NSString * to svar, which is still a char. You then try to send a rangeOfString: message to svar, which should be sent to a NSString * (or at least an NSObject *). This is also likely to cause a crash. Your if condition seems OK, assuming you want to test that hejhej was contained in the result (if you've managed not to crash, though, I don't believe this will ever be true). Your NSLog seems fine (are you swearing at the user?). Is userIsAlive a bool or BOOL? The latter is more common, and YES and NO are the normal values used.
I can guess what waitOnCR does, but it seems to be used a bit too much.
Where are you learning from? What is your ultimate goal? Right now the gist seems to be to read from the console and, if the input contains hejhej, insult the user. You've got quite a ways to go. At the very least you need to read into a char[] and you need a new variable to store your NSString *. This isn't actually a complete function or program so there may be other bugs in code you didn't include.
Keep at it, and post your updated code. Please try to post code in at least self-contained functions if not complete programs. This allows others to test your code more easily. Also include what you want your code to do, what you think your current code should do, and what it actually does. If you have tried other approaches, details those and why you abandon them.
-Lee