US citizen flying from Spain to Toronto with a Spaniard- customs/border difficulties?

I'm a US citizen from Buffalo and I'll be flying into Toronto next week with my Spanish partner. My dad is picking us up from the Toronto airport and we're driving to Buffalo. My questions are:
Does my Spanish partner have to do anything special to enter Canada, like an ESTA form? He has his ESTA for crossing into the US.
If we have 5 bottles of wine between the two of us, is that ok? Is there a limit? If we have to pay duty on one of the bottles (say the limit is 2 per person), how much will it cost?
Thanks for any help!
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Do I clear US customs in Toronto?
U.S. Customs and Immigration preclearance: passengers travelling between points in the U.S. and Europe, Israel or Asia can complete U.S. Customs and Immigration formalities in Toronto, thus saving time on arrival at their final destination in the U.S., where their arrival is treated as a domestic flight.How long does it take to clear US customs in Toronto?
As a rule 90 minutes should be sufficient.These Countries will DENY ENTRY at Immigration. Vacation Disasters
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