I have a "page" or "post" that I can not find anywhere. I would like to delete it, but I can not find it anywhere. I have already looked at the list of posts and pages, and even the database.
Follow the link on the page ...
This is attachment, you can find it in the Dashboard > Media menu. which id is: 497, you can find it and delete it. As I can see in Inspect element this is image: http://capptan.com.br/blog/wp-content/uploads/2018/07/engajar-e-reter-usu%C3%A1rios-de-aplicativos.jpg
But in your template, I can see you have hidden these things via CSS.
Hope you know how to delete it from Media.