If these requirements are met, Just insert the Office DVD into the computer DVD drive. If the installation starts normally, continue by following the screen prompts. Use default settings if you are not familiar with the custom settings. And, do a full (complete) install.
If the program does not start when you insert the Office DVD, then open Windows Explorer. Select the DVD drive. You will find an 'Install' icon. Double click and the install icon and follow the on-screen prompts.
After the install is complete, proceed with the activation, using the code provided with the software. This code will be on the Office packaging.
Another way to install the software is to read the instructions on the package.