How to create column for attachment in SharePoint 2013 Document Library.

Question

I've created document Library where user can upload the file while click on Upload option (OOTB).
Now in this Library I want to create one more column where user can put some comment and attach one more file for reference. 
For comment I can create "Single line of text" type calumn where user can put some comment but for attachment not sure which type of column I have to create.
Want to know is there OOTB feature/column available which I can use to Add / create a one more column to upload a document for reference.

Answer 1

Hi,
For issue 1, please refer 
To manage the permissions for a Document Set, you must have at least the Design or Full Control permission level.
On the Welcome Page for the Document Set, click the Manage tab of the Document Set ribbon, and then click Permissions.
Do one of the following:
To change the permission settings for the document library itself, click Manage Parent.
To stop inheriting permissions from the document library and create unique permissions for this Document Set individually, click Stop Inheriting Permissions.
To view the specific permissions an individual has, click Check Permissions, and then type the name of the user or group you want to check.
To inherit permissions from the parent document library (if the Document Set was previously configured to stop inheriting them) click Inherit Permissions.
For more information about working with permissions, see the links under See Also.
https://support.office.com/en-in/article/Create-and-manage-Document-Sets-c71d5796-d559-48de-b1b3-42383bdd13ea?ui=en-US&rs=en-IN&ad=IN
For Issue 2:
You can create a link in the Quick Launch bar
http://support.sherweb.com/Faqs/Show/how-to-add-a-link-to-the-quick-launch-toolbar-in-sharepoint-sharepoint-2013
Please don't forget to mark it answered, if your problem resolved or helpful.