You have probably purchased a product without a USB-C power adapter.
If you already have USB power adapters in your home or office, you do not need to purchase a product with a power adapter.
However, make sure that the cable included with the device is compatible with your power adapter.
See also "Compatible power adapters" and "Compatible USB-C cable".
The EU has stipulated in Directive (EU) 2022/2380 that manufacturers must give consumers the choice of whether they need a charger. This prevents unnecessary electronic waste.