Need to connect 24 drives what are my best options with these parts?

You can find the LSI SAS cards you need in the recent guides, typically in the “other parts” section.

Since you have an 846A, your options are to run 3 of the LSI 8i cards (doesn’t matter which, whether it’s 9201/9210/9211) or run a single LSI 8i with a single HP SAS expander.