How to distinguish pages created by woocommerce?

You can use conditional tags or function wc_get_page_id('page_name'), where page_name can be: ‘myaccount‘, ‘shop‘, ‘cart‘, ‘checkout‘, etc.

For example:
Using is_cart() you can check whether the current page is a cart page.
Using wc_get_page_id( 'cart' ); you will receive ID of cart page.

Which way is more suitable for your code you have to decide for yourself. Some conditional tags ( like is_checkout(), is_cart() ) are based on wc_get_page_id().