Failed and uncreated pilots

First off I apologize if I fail at fully explaining any of this.
I plan to start a website that is generally a dispensary of cartoons, webcomics, and anything else I can think of. I of course plan to make my own comics and webcomics, but I also want to take ideas people have already thought of but haven't had the means to make themselves (such as failed pilots and cartoons started on YouTube that couldn't get off the ground even though they had potential) along with stuff that's pitched to me and passes a screening. My question is how or if I could buy pilots like "Constant Payne" or "Urbance".
Constant Payne pilot: https://youtu.be/o7fR6gLQ2C8
Urbance: https://youtu.be/8F_rXxp6KY8 (this one i mainly like for the animation but the story is a bit ummm...i don't know how to put it)
Also if you have any advice for my idea that'd I'd be very appreciative.