I want to create a post in my web site and post/share it in my Facebook page. This can be live/video/image etc. The amount likes and reaction my post get in Facebook will need to be fetched and stored in my post related database of my website.
The easiest solution would be to save the post ID when you create a post (Which you will get if the post was successfully created via the API) docs
And when you want to get the likes, use that post ID and fetch the API for the information. docs