Maybe i can help you with this.
You could use an RSS feed to take the articles from other sites and post them on your site, but this would be more a plugin solution than a script solution. I'm not sure if you are using Wordpress, PHP, or JS for this, but if you want just send me your telegram user name on PM and lets have a talk about it.
The part about posting on Facebook is simple with RSS too... So, let's see if i can i help you.
dont the website im taking this from need to have rss enabled too?