An output style (or bibliographic style) is a template that tells EndNote how to format the citations in a manuscript or bibliography. EndNote includes over 2,800 automatically-created output styles (APA, AMA, NLM, Vancouver, Chicago, etc.). Additional styles can be downloaded from the EndNote Website.
If you find the journal style you need, download the file and save to the desktop.
If you cannot find the output style you need from the EndNote website, you can alter an existing style to conform to your needs.