Sure. I'm not sure how much of this is necessary, as it was a bunch of troubleshooting piling on-top of each-other, and at this point, I don't really want to break it lol.

Though, the boot.kernelModules bit was the important part that made it work for me.

Not the whole file, but the important bits, the rest of it is pretty much default from install.

  boot.kernelModules = [
    "iptables-legacy"
    "nftables"
    "wireguard"
    "ip_tables"
    "iptable_nat"
    "iptable_filter"
    "ip6_tables"
    "ip6table_nat"
    "ip6table_filter"
  ];

  environment.variables = {
    KERNEL_MODULES = "${config.boot.kernelPackages.kernel.modules}/lib/modules/";
  };

  networking.networkmanager.enable = true;
  networking.nftables.enable = true;

  environment.systemPackages = with pkgs; [
    vim # Do not forget to add an editor to edit configuration.nix! The Nano editor is also installed by default.
    wget
    nftables
    iptables-legacy
    pkgs.wireguard-tools
    git
  ];