Application for calculating the prices of selected products?

Question

JavaScript

I am interested in the algorithm for creating the following application: there is a clothing catalog, it is necessary that when you click on the variable array, the price of the selected product is added (several of them will be selected). This is necessary in order to calculate the total price when buying these things.
Most of all, I'm interested in how to add the price of the product to the variable array when clicking on the image.
I would be grateful for the description of the algorithm.
Server side in php/java Client in JavaScript

Answer 1

For example, assign a data-attribute to a picture, write a value there and, when clicked, pick it up and write it to an array