Enable Page Rule (Cache Level - Cache Everything) except for dynamic elements

I would like to enable a page rule - cache everything. But i would like to exclude dynamic elements such as the cart counter in the menu and a configurator we run on the website.

The rule we want to enable is this one:

And the things we would like to exclude are:
the cart counter in the menu. Because if we don’t it caches the cart counters of visitors which will be displayed from the cache serving all visitors

We would also like to exclude the configurator https://shirt-discounter.nl/heren-t-shirt-ronde-hals-bedrukken-e150/?start_customizing the url for this configurator always ends with /?start_customizing https://shirt-discounter.nl/k479-unisex-vest-bedrukken/?start_customizing

Cloudflare cache goes by URL, so it can not cache or exclude portions of a response.

As far as start_customizing, you can create a Cache Rule to bypass with Query String contains: