Customize Wordpress Plugins II

Hi all! I have a website in WordPress + Woocommerce + Dokan Multi Vendor Plugin Here the link for Dokan MV [login to view URL] The theme chosen is this [login to view URL] This the result: [login to view URL] The project is a marketplace for booksellers. My need is to add customizations to the front-end for adding functions to plugin called Dokan. PLEASE READ VERY CAREFULLY. A - (See the attachment) On the entry of new products, there are various options. I need that: • the stock quantity must be 1 by default; • the weight must be 0.5 Kg by default; Creating a new section to the Dokan plugin settings called "Shipping" and : B - (See the attachment) Possibility of including free shipping when you exceed a certain quantity of products in the cart. Ba - (See the attachment) Possibility of including free shipping when you exceed a certain amount (in €) in the cart. C - (See the attachment) Possibility of including a packaging cost per book. D - (See the attachment) Pick up by hand available on cart only If selected by the seller. E - In addition there is a bug in a plugin installed to manage privileges of sellers. The plugin called "Dokan Permission Author". The plugin allows you to choose the privileges of the individual seller. At the moment the plugin has malfunctioned that I will explain in detail via chat. Let me know if you have any doubts. Thanks.