Examples of using caldera_forms_submit_complete hook. See -https://calderaforms.com/doc/caldera_forms_submit_complete/

caldera_forms_submit_complete-remote-post.php

<?php
/**
 * Get a field value and send to remote API
 */
add_action( 'caldera_forms_submit_complete', function( $form, $referrer, $process_id ) {
	//change your form ID here
	if( 'cf123..' != $form[ 'ID' ] ) {
		return;
	}

	//change your field ID here
	$data_from_field12345 =   Caldera_Forms::get_field_data( 'fld12345', $form );

	$remote_api = 'http://api.com/api';

	//POST to remote API
	wp_safe_remote_post( $remote_api, array( 'body' => array( 'something' => $data_from_field12345 ) ) );

}, 10, 3 );

caldera_forms_submit_complete-resendemail.php

<?php
add_action( 'caldera_forms_submit_complete', function( $form ){
	global $transdata;
	if( ! empty( $transdata['edit'] ) ){
		$data = null;
		if( ! empty( $transdata[ 'edit' ] ) ){
			$data = $transdata[ 'edit'];
		}
		//note that $data is the submission data used to send the email - you can modify it here if needed.
		Caldera_Forms_Save_Final::do_mailer( $form, $transdata['edit'], $data );
	}
});

save-entry-as-user-meta.php

<?php
/**
 * Save last entry ID, of specific form to user meta
 */
add_action( 'caldera_forms_submit_complete', function( $form, $referrer, $process_id, $entry_id ) {
	//change your form ID here
	if( 'cf123..' != $form[ 'ID' ] ) {
		return;
	}
  
  update_user_meta( get_current_user_id(), '_last_entry_id', $entry_id );

}, 10, 4 );