Hi Alexis,
It all depends on what you what to accomplish and the specifications of the devices that you will be connecting to the cards. The USB-6218 device is a multifunction device for analog I/O, digital I/O and counters. It will be limited as to how much power it can supply, if needed, since it's USB.
The NI CompactDAQ series of devices are chassis that need modules to acquire information. There are different C series modules depending on what you want to accomplish, is more versatile than the USB-6218. There are CompactDAQ chassis that are USB enabled or even ethernet enabled.
You will need to check the specification sheets of the modules and devices that you are interested in and those of the load cells and the drivers to make sure they match and that you can accomplish what you want.
Here is a link for all the cDAQ chassis' available:
https://www.ni.com/en-us/shop/category/compactdaq-chassis.html?productId=118191
And the specification sheet for the USB-6218:
https://www.ni.com/docs/en-US/bundle/usb-6218-specs/page/specs.html
Regards,