If you are an admins of a page, you must be interested in understanding if people are engaging with the content that you publish. Facebook Insights help you to measurements your Page's performance. It helps you to find data about your audience - their demographics, what kind of posts they like, how they are responding to your posts. You are enabled to experiment with different types of posts to see what your audience responds to best. Your Page needs to have at least 30 likes to start seeing insights.
You can access your Insights data through the dashboard, or export it using the Export button in the top right corner.
This video walkthrough will help you get started with Facebook Metrices such us reach, engaged users, talking about this and virality. You can find these metrics in the Page Posts section of Page Insights.
Now that you know how to use Facebook Insights, all you need to do is narrowed down your key metrices and analyse this data. With Facebook insights, you can learn which content resonates with your audience. You can improve upon your content strategy to optimize your page.