SharePoint Permission

Hello! I have SharePoint 2013 on Windows Server 2008 R2. I use Visual Studio 2013 to connect  by SharePoint Object Model for work with SharePoint web servises. Can you, please, tell me "How can I configure the permission to allow some of the windows users to be able to upload/delete/read/write/download or deny access to file or folder in Document Library in current site?" Is this possible? Please, if is possible provide with code on c#.