What is the best way to build a system “make a share of our action - we will put your page on our feed”?

Question

Facebook

I am a project manager, not a professional. I want this for a project: an ad site. You need to have this system -
On the site, the user is offered that if he shares our promotional text on Facebook or OK, then in response our server automatically puts a thumbnail of his page with his ad on our Facebook and OK feeds. He agrees and all this happens, or presses "I DO NOT WANT".
What is the best way to build this system? We plan the site on pure PHP, or on something recognized like Laravel.
Everyone vouches, but I really want to learn from you the most effective method for building the above, and based on this, choose the best candidate to work on the back-end of the project.
Thanks in advance!