If you are a consumer, there is no difference between zero-rated and exempt goods and services because no GST/HST is collected in either case.
If you are a seller and GST/HST registrant, there is difference between zero-rated and exempt goods and services. You can claim ITCs for the GST/HST paid or payable on purchases used to make zero-rated supplies and services. But no ITCs can be claimed for purchases used to make exempt supplies and services.