What version of EN are you using, as some specifics will change in the best way to view various styles available?
You should explore the multitude of different styles that come with Endnote. To view these, from the style drop-down, in Endnote, Choose another style and put some checkmarks in front of the styles you would like to view. Do you have a specific journal you are planning to use? Start there - you change the style thru the format bibliography tool. You start by seeing only a small group of the output styles.
Once you find a style, if there are other changes you would like to make, these are done by editing the style. Finally, if you run into a problem that you aren’t sure about, you can always attach the style to a msg here and tell us what is wrong, and one of us can usually fix it and post it back.
For another source of styles that might help you, see this thread. If you are using X2 or X3, you can just open the attached style which should open in Endnote and save it from Endnote. It will now be listed in your output style manager.