Install MariaDB with phpmyadmin and secure the access to it with .htaccess

Install and secure MariaDB:

apt install mariadb-server
mysql_secure_installation

Install phpmyadmin:

apt install phpmyadmin

Configure phpmyadmin access. Open /usr/share/phpmyadmin/.htaccess and fill it with:

Protect Directory
AuthName "Dialog prompt"
AuthType Basic
AuthUserFile /usr/share/phpmyadmin/.htpasswd
Require valid-user

Create a user admin with password with following command:

htpasswd -c /usr/share/phpmyadmin/.htpasswd admin

Final configuration. Open /etc/apache2/conf-available/phpmyadmin.conf and add to the target directory:

AllowOverride All

Finally, restart Apache:

systemctl restart apache2.service