You can get total related information in the checkout page with a subtotal, shipping charge, grand total using Javascript.
For getting update grand total with the shipping charge and tax total and other info you need to call ‘Magento_Checkout/js/model/totals’ in the JS file.
You need to call totals Objects with a required field,
define([
'uiComponent',
'Magento_Checkout/js/model/totals'
], function (Component,totals) {
'use strict';
return Component.extend({
getGrandTotal: function(){
if (totals.totals()) {
var grandTotal = parseFloat(totals.totals()['grand_total']);
return grandTotal;
}
},
getSubTotal: function(){
if (totals.totals()) {
var subtotal = parseFloat(totals.totals()['subtotal']);
return subtotal;
}
},
getShippingAmount: function(){
if (totals.totals()) {
var shippingAmount = parseFloat(totals.totals()['shipping_amount']);
return shippingAmount;
}
}
});
});
You can call above function in template with getGrandTotal(), getShippingAmount() and getSubTotal().