How to keep WP from creating a “single-post” page and let the user input the link of the post in the dashboard?

How to keep WP from creating a “single-post” page and let the user input the link of the post in the dashboard?

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)