Are you referring to High School or college? If high school, you need to major in as many science courses as possible (chemistry, biology,etc.). If you are referring to college, you will need to take whatever courses are set up for the nursing degree plan. As for salary, I know many staff nurses making $50,000/yr or better. CRNA's make more because of their increased liability and education required. In my state the CRNA's are required to have a minimum of 2 years as a nurse in a critical care area, so your first step is to get the RN license. There is MUCH MORE to professional nursing than money. I hope you base your career goals on how suitable the profession is for you personally. BTW, the fact that you are seeking information indicates you would make a good nurse because nurses have to plan ahead.
P.S. Use lower case letters please. Upper care infers "shouting"