It means that it is impossible to get something for nothing, or the idea that even if something seems free, there is always a cost, no matter how indirect or hidden the cost is.
The feeling would be more of a touch feeling. We can tell that it would be a touch feeling because it describes the feeling of being hot, or the feeling of steam.
It's asking you how your reading selection has effected you. did they make you better writer? did you become more perceptive to detail? stuff like that. basically how reading effects you