Change AllowOverride None to AllowOverride All - apache

Question

These two file have the same code inside.
/etc/apache2/sites-enabled/000-default
/etc/apache2/sites-available/default
I would like to change AllowOverride None to AllowOverride All.
Which file should I change？
Is all the AllowOverride None change to AllowOverride All?
<VirtualHost *:80>
DocumentRoot /var/www/drupal
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
<Directory /var/www/drupal>
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
</Directory>
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
<Directory "/usr/lib/cgi-bin">
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
</Directory>
ErrorLog ${APACHE_LOG_DIR}/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog ${APACHE_LOG_DIR}/access.log combined
Alias /doc/ "/usr/share/doc/"
<Directory "/usr/share/doc/">
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
</Directory>
</VirtualHost>

Answer 1

/etc/apache2/sites-enabled/000-default
/etc/apache2/sites-available/default
Actually these are not 2 files. One is a symlink of the other. So that is why they are exactly the same.
The sites-available just shows which sites you have on your system. But sites-enabled show which one's are in use.
So just change the original in sites-available because they are the same file. And yes use AllowOverride All to enable .htaccess use under <Directory /var/www/drupal> block.
You can use commands a2ensite and a2dissite to enable and disable sites if you add more later. The link below gives exact instructions if you ever need to do that, which you shouldn't since your site is live.
http://manpages.ubuntu.com/manpages/trusty/man8/a2ensite.8.html