Please refer to Woocommerce documentation https://docs.woocommerce.com/document/change-add-to-cart-button-text/
In this case, we recommend using the Child Theme.
We have already created and included child theme in theme package. You just need to find royal-child folder in theme package and upload it to /wp-content/themes/ folder and you’ll see there the function.php file.
Try to go to Woocommerce > Settings > Accounts and check account settings there.