First be logged as a JIRA administrator and then click on the visible only to such user cog icon to access "Projects":
In order to export projects to Excel perform "export to Excel" action:
Evaluation only license warning:
You have evaluation license - it allows to export only 5 users. Please purchase full license to be able to take full advantage of the Admin Tools for JIRA.
The export form wizard open. Select a field you want to export. Order of the fields can be changed by drag and drop technique. Order of the chosen ones is to be present in the generated Excel spreadsheet.
Press"Save File" button to download Excel file at a desired location.