Instead of installing packages through a package manager one at a time and configuring your system by digging into individual config files, NixOS has you write a single config file with all your settings and programs declared. This lets you more easily configure your system and have a completely reproducible system by just copying your nix files to another nixos machine and rebuilding.
It’s also an immutable distribution, so the base system files are only modified when rebuilding the whole system from your config, but during runtime it’s read only for security and stability.
Linux NTFS support is pretty good. The kernel drivers do all the basics, but you may still want the ntfs-3g driver installed for some of its tools. Ntfsfix has saved me before and I think it’s from the ntfs-3g package