Update dotnet-restore.md (#46597)

Author: marcpopMSFT

docs/core/tools/dotnet-restore.md

@@ -21,7 +21,7 @@ dotnet restore [<ROOT>] [--configfile <FILE>] [--disable-build-servers]
     [--no-cache] [--no-dependencies] [--packages <PACKAGES_DIRECTORY>]
     [-r|--runtime <RUNTIME_IDENTIFIER>] [-s|--source <SOURCE>]
     [--tl:[auto|on|off]] [--use-current-runtime, --ucr [true|false]]
-    [--use-lock-file] [-v|--verbosity <LEVEL>]
+    [--use-lock-file] [-a|--arch <ARCHITECTURE>] [--os <OS>] [-v|--verbosity <LEVEL>]
 
 dotnet restore -h|--help
 ```
@@ -156,6 +156,18 @@ There are three specific settings that `dotnet restore` ignores:
 
   Enables project lock file to be generated and used with restore.
 
+- **`-a|--arch`**
+
+  Specifies the target architecture.This is a shorthand syntax for setting the Runtime Identifier (RID), where the provided value is combined with the default RID. For example, on a `win-x64` machine, specifying `--arch arm64` sets the RID to `win-arm64`.
+
+  Introduced in .NET SDK 8.0.100
+
+- **`--os`**
+
+  Specifies the target operating system (OS).This is a shorthand syntax for setting the Runtime Identifier (RID), where the provided value is combined with the default RID. For example, on a `win-x64` machine, specifying `--os linux` sets the RID to `linux-x64`.
+
+  Introduced in .NET SDK 10.0.100
+
 [!INCLUDE [verbosity](../../../includes/cli-verbosity-minimal.md)]
 
 ## Examples