Thanks for providing the bnsupport bundle. I can see a recurrent error message in the Apache error log:
PHP message: PHP Warning: include_once(/opt/bitnami/apps/wordpress/htdocs/wp-content/themes/storefront/woocommerce/class-wc-widget-cart.php): failed to open stream: No such file or directory in /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/roadthemes-helper/roadthemes-helper.php on line 487
PHP message: PHP Warning: include_once(): Failed opening '/opt/bitnami/apps/wordpress/htdocs/wp-content/themes/storefront/woocommerce/class-wc-widget-cart.php' for inclusion (include_path='.:/opt/bitnami/php/lib/php') in /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/roadthemes-helper/roadthemes-helper.php on line 487
PHP message: PHP Fatal error: Uncaught Error: Class 'Custom_WC_Widget_Cart' not found in /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-widget-factory.php:100
#0 /opt/bitnami/apps/wordpress/htdocs/wp-includes/widgets.php(115): WP_Widget_Factory->register('Custom_WC_Widge...')
#1 /opt/bitnami/apps/wordpress/htdocs/wp-content/plugins/roadthemes-helper/roadthemes-helper.php(488): register_widget('Custom_WC_Widge...')
#2 /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-hook.php(286): sinrato_override_woocommerce_widgets('')
#3 /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL, Array)
#4 /opt/bitnami/apps/wordpress/htdocs/wp-includes/plugin.php(465): WP_Hook->do_action(Array)
#5 /opt/bitnami/apps/wordpress/htdocs/wp-includes/widgets.php(1715): do_action('widgets_init')
#6 /opt/bitnami/apps/wordpress/htdocs/wp-includes/class-wp-hook.php(286): wp_widgets_init('')
This seems to indicate an incompatibility with the plugin you are trying to use. Please ensure the version that you installed is compatible with the WordPress version running in your server.
In order to revert to your previous theme, you could try directly changing the database values using this command:
mysql -u root -p bitnami_wordpress -e 'UPDATE wp_options SET option_value="twentynineteen" WHERE option_name IN ("template", "stylesheet");'
twentyseventeen, as it was the default theme in WordPress 4.9, and is also present in newer versions. Feel free to change it to a different value.
Also, you can get the current value for those settings using this other command (before executing the above one):
mysql -u root -p bitnami_wordpress -e 'SELECT * FROM wp_options WHERE option_name IN ("template", "stylesheet");'