Show the excerpt in a loop

get_the_excerpt function has issues using it with wp_get_recent_posts so instead of get_the_excerpt function use wp_trim_excerpt function in your code as displayed below.

<?php
    $args = array( 'numberposts' => '3' );
    $recent_posts = wp_get_recent_posts( $args );
    foreach( $recent_posts as $recent ){
    ?>
    <div class="wpb_column vc_column_container vc_col-sm-4">
        <div class="wpb_wrapper">
            <div class="wpb_text_column wpb_content_element  wpb_animate_when_almost_visible wpb_left-to-right wpb_start_animation">
                <div class="wpb_wrapper">
                    <p>
                        <a href="https://wordpress.stackexchange.com/questions/266575/<?php echo get_permalink($recent["ID"]) ?>">
                            <?php echo get_the_post_thumbnail($recent['ID']); ?>
                        </a>
                    </p>
                    <h3><a href="https://wordpress.stackexchange.com/questions/266575/<?php echo get_permalink($recent["ID"]) ?>"><?php echo $recent["post_title"] ?></a></h3>
                    <p><?php echo wp_trim_words( $recent['post_content'], 50, '...' ); ?></p>
                </div>
            </div>
        </div>
    </div>
    <?php
}
wp_reset_query();
?>