How to make a Wordpress Plugin that allows user to download or convert Online videos from different sites

before I begin I want you guys to know that I don't know anything about PhP or java Programing. I am an iOS Developer. Only Know Swift so far. I was trying to make my first website using only plugins without programing but Its getting complicated for me because I was planning to open a website like http://ift.tt/Rivd0C or http://ift.tt/24Vds6M, where I let the user download any videos from as many websites as possible. But its difficult for me as I don't know any php coding yet and there are no plugins out there where I can just integrate. It would be really appreciated if anybody here has an example of a video downloader or any plugin for me to get started.I am using Wordpress by the way. Thank you very much for your time. :)

via Chebli Mohamed