You will have to forgive me as I'm not real knowledgeable about shotgun ammunition except for bird shot, buck shot and slugs, lol. I bought about 100rnds of shotgun ammo for $10 at a garage sale. Had a mix batch of ammo, but I don't know what its purpose is.
Have about 3/4 a box of #5 shot
several BB loads and 5 Activ all plastic rounds. What are they for?

I would guess the #5 is for something like pheasant, and the BB for waterfowl if it’s steel.

Here is a good chart



General rule of thumb is larger the animal the larger shot

5 would work on turkey (head shots), pheasant, small game like rabbit too

Bb for ducks as said if steel. Be careful if it’s the old school lead or copper shot as that’s illegal to hunt waterfowl