how to convert 32 bit photos to newer Mac systems

Have you been storing your photos in iPhoto Libraries? If yes, which version of iPhoto have you used?

On macOS 13 you can import photos from iPhoto Libraries iPhotos Libraries into an existing Photos Library, unless the library has been created with iPhoto 7.x.x or earlier. Older iPhoto Libraries need to be prepared with iPhoto Library upgrader tool, and this tool can only run on macOS 10.14 or older system versions.

Even, if you can import from an old iPhoto Library, you may not be able to import photos or videos in a legacy format. The 64-bit only versions of Mac OS (since macOS 10.15 Catalina) do not support all media formats, that could be imported to iPhoto or Photos on earlier system versions. These older media should have been converted to a more compatible format while you have been running a system version that supported these formats, see for example this list for iMove: About legacy media in iMovie for macOS - Apple Support

If you do no longer have a device with a system version that could handle the old formats, you may need to use their-party software to convert the media files, for example Graphic Converter for photos and videos, or HandBrake for videos.

OK, then what makes you think you can't get to them?

If you are trying to do something and get unexpected results, what are you trying to do, how are you trying to do it, and exactly what unexpected results do you get?

Details, please. Remember that we can't see your computer.

We're willing to help but our ability to do so is directly proportional to the information you give us to work with. So let me rephrase my question to you:

So, how are these images stored ? What have you done to try and get access to them, and where has it failed?

There is no such thing as a 32 bit photograph. That refers to applications. So, how are these images stored and why can't yo get to them?