Facebook makes it easy to report any post you find abusive, offensive, or that is against their policies by doing the following steps.
In the top-right corner of every post on the Facebook News Feed, you’ll find a small gray arrow that points down. Click or tap this arrow to open a menu similar to the following example.

Report post
Select the Report Post option that appears in the menu and select the reasons you are reporting the post.
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Once you’ve selected one of the reasons why you are reporting a post, click the Continue button.