I had trouble getting phpbb3 working on the web. It needed a bunch of ports before it displayed and work correctly.
Besure to check you version of php "
www/mod_php72 security/php72-filter archivers/php72-zlib textproc/php72-xml textproc/php72-dom graphics/php72-gd security/php72-openssl converters/php72-iconv databases/php72-pgsql
php --version" should note phpbb3 ports installed with some php extensions but not the ones I listed.