Is it possible to Utilise Own inputs in undertaking job-work. if we doesnot availed Cenvat Credit for the same.? whether the same would amount to manufacture at the time of removal?

From the question it appears that you are doing a job work under law (Rule 16A of CER) and the duty is paid at other end. Also for the job work you are utilising some of your inputs. So far as the manufacturing is under job work and duty liability is with the job provider it does not amount to manufacture for you.