Ubuntu 18.04

Update system
apt -y update && upgrade

Install apache and php
apt install apache2 php7.2 php7.2-common

Backup configuration
mkdir /root/backup
cp -r /etc/apache2 /root/backup/
cp -r /etc/php /root/backup/

Start Apache daemon
systemctl start apache2
systemctl enable apache2

Create directory for each host
mkdir /var/www/host1.darin.web.id
mkdir /var/www/host2.darin.web.id

chown -R www-data:www-data /var/www/host1.darin.web.id/
chown -R www-data:www-data /var/www/host2.darin.web.id/
chmod 755 /var/www/*

Create index file for each host
cat >> /var/www/host1.darin.web.id/index.php
<?php phpinfo();?>
ctrl + c

cat >> /var/www/host2.darin.web.id/index.php
<?php phpinfo();?>
ctrl + c

Configure VirtualHost
cd /etc/apache2/sites-available
cp 000-default.conf host1.darin.web.id.conf
cp 000-default.conf host2.darin.web.id.conf

vim host1.darin.web.id.conf

<VirtualHost *:80>
    ServerAdmin postmaster@darin.web.id
    ServerName host1.darin.web.id
    DocumentRoot /var/www/host1.darin.web.id
    DirectoryIndex index.php

    ErrorLog /var/log/apache2/host1.darin.web.id_error.log
    CustomLog /var/log/apache2/host1.darin.web.id_access.log combined
 </VirtualHost>

vim host2.darin.web.id.conf

<VirtualHost *:80>
    ServerAdmin postmaster@darin.web.id
    ServerName host2.darin.web.id
    DocumentRoot /var/www/host2.darin.web.id
    DirectoryIndex index.php

    ErrorLog /var/log/apache2/host2.darin.web.id_error.log
    CustomLog /var/log/apache2/host2.darin.web.id_access.log combined
 </VirtualHost>

Enable VirtualHost
a2ensite host1.darin.web.id.conf
a2ensite host2.darin.web.id.conf

Enable mod_rewrite
a2enmod rewrite

Restart Apache daemon
apache2 -t
systemctl restart apache2
systemctl enable apache2

Additional notes
If there is any error like variable ${APACHE_x_x} is not defined
Just run command source /etc/apache2/envvars

Click here for the details.