As you don't give a lot of details, I am guessing a little here ... but
Health, person, nursing, and environment are not "key concepts of Watson's Caring Theory." They are the 4 concepts in the nursing meta-paradigm as identified by Jacquiline Fawcett (spelling
of first probably incorrect) -- concepts that are commonly included in one form or another in many theoretical works. They are 4 concepts that are used by many scholars to describe and compare theories. Many textbooks use those 4 concepts to describe, analyze, evaluate, and compare nursing theories. For example, someone might ask, "How do these two theorist view the concept of person differently? What do their ideas about people have in common? etc.)
I suspect that your confusion is stemming from mixing up the concepts that your textbook authors use to discuss/compare theories with actual key concepts emphasized by the theorist herself. Watson's original theory focus on 14 "caring factors." Over time, those evolved into 14 "carative processes." Within those 14 factors, and within additional writings, she talks about people and nursing, etc., but not as cornerstones of her theory.
I hope that helps a little.