There is no definite answer as to how hard managing a WooCommerce website can be. It really depends on various factors such as the size and complexity of your online store, your level of technical expertise, and the amount of time and effort you're willing to put into managing your WooCommerce website.
That said, WooCommerce is a fairly user-friendly platform and even those with little to no technical knowledge can learn how to set up and manage a WooCommerce website with relative ease. There are also plenty of resources available online (including on the WooCommerce website itself) to help you get started and troubleshoot any issues you may encounter.
So overall, while there is no easy answer to how hard managing a WooCommerce website can be, it is certainly possible for anyone to learn how to do it with a bit of time and effort.