Add below functions to your function.php file in WordPress child theme
/*Proceed to Checkout*/

remove_action( 'woocommerce_proceed_to_checkout', 'woocommerce_button_proceed_to_checkout', 20 ); 
add_action('woocommerce_proceed_to_checkout', 'sm_woo_custom_checkout_button_text',20);

function sm_woo_custom_checkout_button_text() {
    $checkout_url = WC()->cart->get_checkout_url();
  ?>
       <a href="<?php echo $checkout_url; ?>" class="checkout-button button alt wc-forward"><?php  _e( 'Check On Out', 'woocommerce' ); ?></a> 
  <?php
} 


/*Add to cart*/
add_filter( 'woocommerce_product_single_add_to_cart_text', 'sm_woo_custom_cart_button_text' );
add_filter( 'woocommerce_product_add_to_cart_text', 'sm_woo_custom_cart_button_text' );   
 
function sm_woo_custom_cart_button_text() {
        return __( 'Add to basket', 'woocommerce' );
}

/*View Cart*/
function sm_text_view_cart_strings( $translated_text, $text, $domain ) {
    switch ( $translated_text ) {
        case 'View Cart' :
            $translated_text = __( 'Check On Out', 'woocommerce' );
            break;
    }
    return $translated_text;
}
add_filter( 'gettext', 'sm_text_view_cart_strings', 20, 3 );