Error message

• Deprecated function: TYPO3\PharStreamWrapper\Manager::initialize(): Implicitly marking parameter $resolver as nullable is deprecated, the explicit nullable type must be used instead in include_once() (line 19 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/file.phar.inc).
• Deprecated function: TYPO3\PharStreamWrapper\Manager::initialize(): Implicitly marking parameter $collection as nullable is deprecated, the explicit nullable type must be used instead in include_once() (line 19 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/file.phar.inc).
• Deprecated function: TYPO3\PharStreamWrapper\Manager::__construct(): Implicitly marking parameter $resolver as nullable is deprecated, the explicit nullable type must be used instead in include_once() (line 19 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/file.phar.inc).
• Deprecated function: TYPO3\PharStreamWrapper\Manager::__construct(): Implicitly marking parameter $collection as nullable is deprecated, the explicit nullable type must be used instead in include_once() (line 19 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/file.phar.inc).
• Warning: ini_set(): Session ini settings cannot be changed after headers have already been sent in include_once() (line 344 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/sites/default/settings.php).
• Warning: ini_set(): Session ini settings cannot be changed after headers have already been sent in include_once() (line 345 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/sites/default/settings.php).
• Warning: ini_set(): Session ini settings cannot be changed after headers have already been sent in include_once() (line 353 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/sites/default/settings.php).
• Warning: ini_set(): Session ini settings cannot be changed after headers have already been sent in include_once() (line 360 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/sites/default/settings.php).
• Warning: ini_set(): Session ini settings cannot be changed after headers have already been sent in drupal_settings_initialize() (line 826 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/bootstrap.inc).
• Warning: session_name(): Session name cannot be changed after headers have already been sent in drupal_settings_initialize() (line 838 of /is/htdocs/wp1175148_PQEGCSGYW9/www/stuhm/dpl/includes/bootstrap.inc).