You can delete only custom fields. Defaults fields in Vtiger CRM cannot be deleted.
Note: You can delete a field only if you are an Admin user.
Follow these steps to delete a field:
- Click your display picture on the top right corner of the screen.
- Click Settings.
- Go to Module Layouts & Fields under Module Management.
- Select the module whose field you want to delete from the Select Module drop-down.
- Click the Detail View Layout tab.
- Hover over the field that you want to delete and click the Delete icon.
- Type 'DELETE' in the textbox provided.
- Click the Delete field.