using bellow php code you can change the Place Order button text
/**
* Change "Place Order" Button text WooCommerce Checkout
*/
add_filter('woocommerce_order_button_text', 'wpdumi_checkout_button_text');
function wpdumi_checkout_button_text($button_text)
{
return 'Purchase';
}
An all round web designer building websites Over 18 years. Interested in achieving a suitable placement in the field of IT in a growth oriented organization which offers diverse job responsibilities in order to utilize and improve my skills, Knowledge and experience.