Need to access old iPhoto pic/library

The last system version, where you could convert an iPhoto Library to a Photos Library has been macOS 12 Monterey. You have missed this window of opportunity by waiting to long.

On macOS Ventura you can use the method suggested by Yer_man in the previous reply and import photos from an iPhoto Library to Photos. This will let you see the photos, but not the albums or events. The structure of the library will be lost. But this will only be feasable, if the iPhoto Library is small. It will take a very long time, to prepare the library for importing from it, if the iPhoto Library is large, or Photos my even crash for want of enough memory. For example, trying to open an Aperture library of 220GB is hanging for 15 minutes on the "preparing" command.

Alternately, you can use a third-party app "PowerPhotos" to convert iPhoto Libraries to Photos Libraries. This is a new feature in the most recent version of PowerPhotos.

How to access Media in iPhoto Libraries on macOS 10.15 or later… - Apple Community

Photos v8, which comes with Ventura can import images from old iPhoto libraries using the file -> Import command.