Cheapest way to store 1TB of data so I can move Windows to my 1TB SSD?

Hey everyone,

I recently found out that I have a 1TB SSD installed in my PC, but it wasn't showing up properly before. I checked it now, and it has around 1TB of my data on it, so it's basically full.

Currently, my Windows is installed on a 256GB SATA SSD, and I want to move/install Windows on the 1TB SSD for better performance and more space.

The problem is that I need to move the existing 1TB of data somewhere else first so I can empty the SSD.

What would be the cheapest reliable option for storing around 1TB of data?

Should I buy a used 1TB HDD, a new HDD, or an external hard drive? I don't need it for gaming or anything performance-related — I just need somewhere safe to store this data.