To add Definition Fields to your Module or Content Item click the '+ Add Field' button shown below.
Then do the following:
1. Enter Field Label and Description
2. Select if you want the field to be Required and/or Displayed - by default the field is not required and the field is displayed
3. Select the Text Field Type
4. To add restrictions and validations like File Size, Image Width & Height to Images, you can specify parameters in Field Properties - these are not required fields but are recommended for best practice
5. If you want to further customize File Types Validation Message, File Types, or select Default File(s) and/or Default Upload Folder(s) expand Advanced Settings
6. Click 'Add Field' and you are DONE!