what is plugin magento 2 or what is interceptor in magento 2

To create a note field in the system configuration page of a Magento 2 module using system.xml, you can use the label and comment tags. Here's an example:

<field id="my_note_field" translate="label" type="note" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1"> 
<label> My Note Field </label> <comment>
This is my note field. It can be used to display additional information or instructions to the user.
</comment> </field>

In this example, the id attribute specifies the identifier for the field, which can be used to retrieve its value programmatically. The type attribute is set to note, which indicates that this is a note field. The sortOrder attribute determines the position of the field relative to other fields on the page.

The label tag specifies the label for the field that is displayed on the configuration page. The comment tag provides additional information or instructions about the field. This comment will be displayed below the label in a smaller font.

The showInDefault, showInWebsite, and showInStore attributes determine whether the field should be displayed on the default configuration page, website configuration page, and store configuration page, respectively. In this example, the field is set to be displayed on all three pages.

Once you have added this code to your system.xml file, you can run bin/magento cache:flush to clear the cache and see the note field on the system configuration page for your module.