Document the project.json migrator (#3389)

Author: nkolev92

docs/archive/media/project-json-migrator.png

@@ -10,7 +10,8 @@ ms.topic: conceptual
 # project.json and UWP
 
 > [!Important]
-> This content is deprecated. Projects should use either the `packages.config` or PackageReference formats.
+> This content is deprecated. Projects should use the PackageReference formats.
+> Learn how to [migrate your project.json project to PackageReference](./project-json.md#migrate-projectjson-to-packagereference).
 
 This document describes the package structure that employs features in NuGet 3+ (Visual Studio 2015 and later). The `minClientVersion` property of your `.nuspec` can be used to state that you require the features described here by setting it to 3.1.
 

docs/archive/project-json-and-uwp.md

@@ -10,7 +10,8 @@ ms.topic: conceptual
 # Impact of project.json when creating packages
 
 > [!Important]
-> This content is deprecated. Projects should use either the `packages.config` or PackageReference formats.
+> This content is deprecated. Projects should use the PackageReference formats.
+> Learn how to [migrate your project.json project to PackageReference](./project-json.md#migrate-projectjson-to-packagereference).
 
 The `project.json` system used in NuGet 3+ affects package authors in several ways as described in the following sections.
 

docs/archive/project-json-impact.md

@@ -10,9 +10,10 @@ ms.topic: reference
 # project.json reference
 
 > [!Important]
-> This content is deprecated. Projects should use either the `packages.config` or PackageReference formats.
+> This content is deprecated. Projects should use the PackageReference formats.
+> Learn how to [migrate your project.json project to PackageReference](#migrate-projectjson-to-packagereference).
 
-*NuGet 3.x+*
+*NuGet 3.x*
 
 The `project.json` file maintains a list of packages used in a project, known as a package management format. It supersedes `packages.config` but is in turn superseded by [PackageReference](../consume-packages/package-references-in-project-files.md) with NuGet 4.0+.
 
@@ -37,6 +38,18 @@ The [`project.lock.json`](#projectlockjson) file (described below) is also used
 }
 ```
 
+## Migrate project.json to PackageReference
+
+The migration between project.json and PackageReference is straightforward. The easiest way to do it to use the built-in migrator in the latest Visual Studio 2022, Update 14.
+
+1. Load the project.json project in Visual Studio.
+1. Go to the solution explorer of the project.json project and find the dependencies node.
+1. Click `Migrate project.json to PackageReference...`!
+
+![Migrating from project.json to PackageReference](media/project-json-migrator.png)
+
+Alternatively, you may use the [dotnet migrate](/dotnet/core/tools/dotnet-migrate), or do the migration manually by taking all of the content from the project.json file and replacing it with the equivalent [PackageReference syntax](../consume-packages/Package-References-in-Project-Files.md).
+
 ## Dependencies
 
 Lists the NuGet package dependencies of your project in the following form: