CS3 is 32-bit software. Modern macOS versions (Catalina 10.15 and later) do not support 32-bit apps.
Perhaps the "in" in your query is followed by "Windows 11," "my old hard drive," "the cloud," or "legal waters." Regardless of what follows the preposition, you have encountered a unique problem: You need a piece of software released in —an 18-year-old application—to run on modern hardware. Searching for- Adobe Photoshop CS3 in-
You may be able to get CS3 running by bypassing modern restrictions: CS3 is 32-bit software