I am thinking of buying an XPS 8950 = 12th Gen Intel Core i9-12900K, 32GB, 2x16 GB DDR5, 1TB M.2 PCIe NVMe SSD.

Obviously 1TB isn't enough but as I am in the UK Dell do not give any option to increase or add drives to their XPS systems, they only sell ready made machines unless you go for Game machines but even then the selection is rather limited and more expensive.

So my question is that I would want to add my existing 2TB SSD Crucial drive and maybe another 4TB SATA drive. I believe there should be slots to do this but will there be the power and data cables already there and will I have to do anything for the system to 'see' these drives?