Upvote:1
You will need a visa for the US. Transit as a concept does not exist in US Airports, and as a result, everyone either needs US Citizenship, an ESTA (Visa Waiver) if part of the list of countries eligible for the Visa Waiver Program in the Unites States.
Seeing as you're from Lagos (Nigerian citizen I assume?), you aren't eligible for the VWP, and as such require a Class C Visa for transiting in the US to get to Canada.