You use CS3. Your client uses Illustrator 2025. They will complain that your file is "out of date."
Since CS3 is no longer actively supported, official resources are limited to archived content: Adobe Illustrator Cs3 Google Drive
You cannot run Illustrator CS3 from Google Drive. The software requires registry entries, system libraries, and activation servers that Drive cannot provide. You use CS3
: For installation and troubleshooting specifics, the CS3 Read Me provides late-breaking information. you get tofu squares.
CS3 does not support variable fonts or modern cloud fonts (like Adobe Fonts). When you open a file saved from Illustrator 2024 in CS3, you get tofu squares.