Restriction: This topic does not apply to Autodesk products that provide each language version on separate media. For these products, you must specify the product language when purchasing, and cannot change it.
For some Autodesk products, such as AutoCAD, you can select the product language at the time of installation, using this drop-down menu on the installer:

Language Selection Menu
If the language you want is not on this menu, your available options vary by Autodesk product. Some products, such as Inventor, use language packs to support additional languages.
These conditions apply to language selection:
- Each suite installation uses a single language. If you need to install one or more products in a different language, that requires a separate installation.
- All deployments must be in a single language. One administrative image can support deployments for different languages, but each deployment is for one language.
- If you are installing multiple products and select a language that is not supported by some products, these products use a default language.
- After you leave the Product Information page of the installer, the menu for selecting a language or adding a language pack is disabled. If you later decide to change the language or add a language pack, you cannot go back to the Product Information page and use the menu. Instead, you must cancel the installation, start the installer again, and then make the correct language selection on the Product Information page.
About Language Packs
A language pack is a software module that can be added to an Autodesk product to change the language used throughout the user interface and the documentation. A single instance of the product software can support multiple languages by adding language packs. Each language pack is matched to a specific Autodesk product, and includes an installer. You must install the Autodesk product before installing a language pack. Each installed language pack creates a separate icon on the Windows Start menu, such as "Inventor - French (Francais)" that you can use to start the product in that language. Depending on your product, language packs may be available on the installation media or from a website.
A language pack installer provides an option to create a language pack deployment for a particular product. The language pack deployment can be installed on multiple computers, after the related product is installed, to add another language version.