nuget is not a recognized as an internal or external command

Instead of using nuget.exe in your path, use .net version dotnet nuget

1. Download the Nuget Exe, keep it in a folder you want to. For ex : D:\Software\Nuget
2. Open Cmd prompt with the same path.

3. To create this .nuspec file, execute the following command in a command prompt.

   D:\Software\Nuget>Nuget.exe spec

For .NET Core / .NET 5:

Use the command dotnet pack

Instead of using a .nuspec file you set those properties in your .csproj file, for example:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net5.0</TargetFramework>
    <PackageId>MyCompany.Project</PackageId>
    <Version>1.0.0.1</Version>
  </PropertyGroup>

...

</Project>

With above config, running dotnet pack will create a file named

MyCompany.Project.1.0.0.1.nupkg

For more details and config options, see: https://docs.microsoft.com/en-us/nuget/reference/msbuild-targets#pack-target

I follow this link and it work fine with me

How to Fix “not recognized as an internal or external command” in Windows

just add the path of the nuget in the path variable

1 - Installing Package:

I followed this Microsoft documentation. Use the nuget.exe CLI in the package console

Note:- This configuration is specific to a project and this adds dependency to the projects package.config

2 - Installing exe:

You can also follow the below documentation, again from Microsoft to download and set the path to nuget.exe folder, as others in this thread has explained. NuGet CLI reference