Question

Is this proper APA citation? Cite the author and date once, then use page number only until citation of author changes?

As the largest group of health care providers and because of their intimate relationships with diverse populations, nurses have an opportunity to play a key role in the transformation of the way health care is delivered in the United States (Institute of Medicine, 2011, p. 2). The RWJF in partnership with the Institute of Medicine (IOM) developed a report than not only studied the ability of nurses to meet the population’s healthcare needs in a reformed health care environ

Answer 1

Well to cite things I wold go to www.easybib.com all yo do is type stuff in a they cite it for youit is very simple

Answer 2

Is the first part of the citation where you list a page number a quote? If not, then you don't need the page. In which case, you can likely just cite the paragraph one time at the end. The exception to that would be multiple quotes, in which case you would do the full citation first, then a truncated one second.
http://owl.english.purdue.edu/owl/resource/560/02/