From where can I get the Extra Order & Product Fees extension?
You can get the Extra Order & Product Fees extension from here
Which commands are required to run after installing the Extra Order & Product Fees extension?
php bin/magento module:enable Magediary_ExtraFees php bin/magento setup:upgrade php bin/magento setup:di:compile php bin/magento cache:flush php bin/magento setup:static-content:deploy
How do the customer and admin know which fees are applied?
The applied fees line shows under the totals block on the following pages, so the customer and admin get it easily by looking in the order totals block. Order Invoice Shipment Credit memo PDF Email Reference ...
Which are the supported input types in the fees selection form?
Supported input field types are: Checkbox Radio Dropdown Hidden Reference guide: https://magediary.com/docs/extra-order-product-fees.html#fees-information
From where can I get the Product Accessories extension?
You can get the product accessories extension from here. https://magediary.com/product-accessories-for-magento-2.html
From where can I get the Product Questions Answers extension?
You can get the product questions answers extension from here. https://magediary.com/product-questions-answers-for-magento-2.html