wordpress permalinks not working 404 code example

Example 1: wordpress 404 page after migration

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress

Example 2: wordpress permalink not working

Follow the following steps to solve this issue:

1. Open the the Apache virtual file for your domain to make changes:
	sudo nano /etc/apache2/sites-available/mysite.conf

2. Make these additions on the file

  <VirtualHost *:80>
      ServerAdmin webmaster@localhost
      DocumentRoot /var/www/mysite
      ServerName server_domain_name_or_IP
      <Directory /var/www/mysite>
          AllowOverride All
      </Directory>
      . . .
      
3. Save and exit then enable mode rewrite which allows you to modify URLs:
	sudo a2enmod rewrite
    
4. Reload Apache
	sudo service apache2 reload

https://www.digitalocean.com/community/questions/why-aren-t-my-wordpress-permalinks-working