There are different ways to earn money from facebook like facebook video monetization and instant article. Facebook Audience network give you ads for your blog and website and pay money if you associate with facebook instant article. Instant article is like google adsense. To earn money you need a facebook page. If you have popular page you will earn more money. Just register instant article and implement ads code to your blog and website post. It will be more easy if you have WordPress hosted website but you can do this for blogger as well. Once approve, just implement code from audiance network then you can monetize your facebook page post from your blog and website using instant article. Your earning or ads will be displayed only for those visitors who visit your post from facebook app because it's not for desktop views.
Facebook Instant Article
https://instantarticles.fb.com/
Tutorial Video in Nepali - How to Make Money on Facebook using Instant Article-Setup Process -Monetize Your Facebook Page
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