C&C Generals Minimum requirements:
Operating System: Windows 98/2000/ME/XP Processor: Intel Pentium III/AMD Athlon - 800MHz Memory: 128 MB RAM CD-ROM/DVD-ROM Drive: 8x Hard Disk Space: 1.8 GB Graphics Card: 32MB - Nvidia GeForce 2 or ATI Radeon 7500 AGP video card or newer supported Sound Card: 16-bit DirectX 8.1 Compatable Keyboard Mouse Recommended Configuration: Processor: Intel Pentium IV/AMD Athlon - 1.8GHz Memory: 256 MB RAM or more Graphics Card: 64MB - Nvidia GeForce 3 or more recent video card
As long as the computer has came out in the last 10 years, you should be fine.
You can get this game here:
Digital for Ultimate Collection for all C&C (Origin Required and can buy code for it at most major retail stores):
https://www.origin.com/en-us/store/buy/c-c-the-ultimate-collection/pc-download/bundle/standard-edition
Older Physical copies:
First Decade (Tiberian Dawn thru Zero Hour): http://www.amazon.com/Command-Conquer-First-Decade-Pc/dp/B000CPKIT6
Just Generals and Zero Hour Box Set: http://www.amazon.com/Command-Conquer-Generals-Deluxe-Edition
All the mods require the Zero Hour expansion, Which is provided with those bundles.