Customize Content Manager Task flow in WebCenter Portal 12c

Hello Experts,

Having a requirement to show the content from Content Repository in view only and view& Download option of  Main and supporting attachment document.

for each user we are having a unique folder path for document which we need to pass at runtime.

to achieve this requirement we need to customize the content Manager taskflow so please guide me how we can customize Content Manager task flow to achieve the functionality in Web Center Portal 12c.

please guide how we can achieve this functionality.

Thanks

Sanjeev