I cant connect to word press

What kind of installation was performed? What steps were followed?

Did you configure the wp-config.php file with the correct User Name and Password for the Database?

I encountered that error pretty often in the past. Here’s a article I’ve used.

https://www.wpbeginner.com/wp-tutorials/how-to-fix-the-error-establishing-a-database-connection-in-wordpress/

first I installed the word press f?le and extract it on desktop

second I create user name and password in my host then make connection automat?cally (host is make it automatically )

? USE Filezilla to change the wp-config sample file

then I enter with the new blog to wp but when I write the Domain without extenion this message apperas.Error establishing a database connection

I create many blogs and I delete a them so is this could be the reason ?

Ardam,
Step 1: Please make sure you have setup your db credentials properly and if you’re still experiencing issues on your site, follow step 2.
Step 2: Generate a new set of salts.

• Generate Salt: https://api.www.ads-software.com/secret-key/1.1/salt/
• Edit after the following line and replace the existing set of salt with the new one.
  $_default_keys = array(

See if it helps.