If I wanted to have a different audio file on each track in a project, how many tracks could I have? Could there be 32? I don’t know how to find this out for sure.
As many as your computer can handle.
As you approach the limit, you will notice that Audacity starts to become sluggish, and there is a noticeable delay between clicking Play, and playback starting.
just for example
on my laptop with AMD-A8 2,20GHz, 4 GB RAM and W10 64bit, I have a project (song) with 40 tracks 8 minutes long, and it works fine
hope this help 
ciao
ilpelle