You will be building a simple page where people paste youtube video links and be able to download the video in mp4 format.
You wont be building an Api for downloading, you will use an already available json Rest Api. Api link >> [login to view URL]@developers
The site will have only 1 page with a search box to paste video url. The page will look like the google search engine homepage.
This is a relatively easy site provided the api is already available hence am hopping you will be able to deliver the project within 2 days.
Please bid wisely as i do not have more that $16 for this simple webpage.