You can download the licensed product version from the Telerik Control Panel which you can get from Your Account. The Control Panel is a small Windows utility which will notify you when a new version of the Telerik product(s) you have purchased is available. Once you download the product of your choice, run the installer to install it on your machine.
The installer will also install Telerik Visual Studio Extensions, which you can use to keep your projects up-to-date. They notify you of new product versions available and prompt you to run the Telerik Upgrade Wizard to automatically upgrade the references in your project to the latest version.
For detailed information on downloading, installing and upgrading, please check the documentation articles for your product.