A change in the /lib/private/Installer.php file may help
$ timeout = $ this-> isCLI? 0: 120; for example: 300
To change default domain path
/var/www/nextcloud/config/config.php
Nextcloud is installed to /var/www/nextcloud so the paths noted in this thread will need to be adjusted.
Also, ownership to the /var/www/nextcloud directory will need to be given to the webserver user (www-data). I.e. “chown -R www-data:www-data /var/www/nextcloud”.