Knowledge Base - How to remove “Powered By Drupal”

Open: SystemPoweredByBlock.php
Located here:
public_html/core/modules/system/src/Plugin/Block/

Change this:
public function build() {
return ['#markup' => '<span>' . $this->t('Powered by <a href="/:poweredby">Drupal</a>', [':poweredby' => 'https://www.drupal.org']) . '</span>'];
}

To This:
public function build() {
return ['#markup' => ' '];
}

That's All!