Only one Facebook Pixel is needed per store. It can be wise to add a second pixel as a backup (by installing a third party app). In your case though, a pixel can apply to a whole store, not just one product.
If this is for a dropshipping store, only use one facebook pixel for all products unless you have more than like 50-100 sales for a certain product under the same pixel, then I would suggest using a different pixel for a different product.
One FB Pixel for One Store having any type of product(s).
Thanks & Regards
MS Web Designer