The main difference of NixOS to other distros is that you configure your system declaratively. This means that installed system settings (e.g. user accounts, enabled drivers, etc.) programs and potentially also configuration for individual programs is all defined in a single place. The disadvantage of this is that a lot of stuff works differently than on “normal” distros and that it tends to have a rather steep learning curve. Unless you’re prepared to invest a significant amount of time into it, you should not install NixOS.

That being said, the topic is a lot more complex (for example, one can also use the Nix package manager on other distros than NixOS), so if you’re interested, here is some more discussion on the topic:

• https://lemmy.world/post/198362
• https://sh.itjust.works/post/223521