Login to your cPanel then go to File Manager > public_html > now find .htaccess make sure the show hidden files option is turned on if not then turn that on after that just simply edit that .htaccess file and remove all codes and paste the following code.
# 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
