Step 1: Download & Install Red Alert
Click the link below to navigate to CnCNet, where you can download the community installer for Red Alert. This download features both Singleplayer and Multiplayer.
Note: this game has been officially been released as freeware, more information can be found here.
Step 2: Run the installer
The Red Alert installer will guide you through on how to install the game. Make sure you do a full web install when prompted.
Once the installer has finished, you can open the settings tool. In the settings window, you can set your in-game resolution.
Step 3: Play
You now have the ability to play Single player or play online via the CnCNet launcher.