Hook form alter for node add or edit forms in Drupal 9

/**
 * Implements hook_form_BASE_FORM_ID_alter() for node_form.
 */
function drutopia_findit_program_form_node_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  $bundle = $form_state->getFormObject()->getEntity()->bundle();
  if (!in_array($bundle, ['findit_program', 'findit_event'])) {
    return;
  }

  // Do things on the edit form or the content creation form for program or event nodes.

}