OTF fonts and TTF fonts should be installed in your Operating System.
If you want to import character styles, click on the Paragraph Styles or Character Styles panel menu button and then choose Load All Text Styles. From there you navigate to another InDesign document and it opens to a dialog box that lets you select any and all Paragraph and Character styles in that document.
Perhaps what you want is a file (or files) with many pre-defined styles which you can use in other documents by going to either the Character Style or Paragraph Style panel menu and choosing Load Styles...
You can also create any number of styles to be defaults, either by saving them in a template document that you use for other docs, or by defining them with no docments open and they will be availble to all new documents.