URL /wp-admin/ was not found on this server

Hi, I bought a new domain and the WP pack, after the WP installation I am trying to access to wp-admin page for the first time. I have done the same procedure other times for other sites without any problem.
This time each browser I use returns the page 404:
URL /wp-admin/ was not found on this server
I followed several tips by search analog problems on this and other forums, here my attempts with same 404 results:
– removed completely WordPress from softaculous control panel and reinstalled it with and without any personalization (choice of theme, username, and password).
– try to navigate several paths directly (e.g. mydomain.it/public_html/wp-admin/, or my domain.it/wp-admin, etc.)
– try to rename .old the plugin and theme folders

In the following the .htaccess file content (public_html folder)
# BEGIN WordPress
# The directives (lines) between BEGIN WordPress and END WordPress are
# dynamically generated, and should only be modified via WordPress filters.
# Any changes to the directives between these markers will be overwritten.
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ – [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

Can someone help me, please?
Thanks,
Fabio

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