URL buttons homepage cannot be cheanges

Hello! I have Mesmerize theme in combination with WooCommerce. On my homepage I show a productlist per category (WooCommerce widget). I can set up this overview, by tagging the specific category and the right products pop up. Somehow, I cannot change the URL that is behind the black button below this productoverview. They all go to the same link and there is no field to change this? Do I need extra CSS or a plug-in for this?

Thank you in advance for your help

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