Hi, I am trying to complete the Agentblazer Champion and I am at "Learn About Agentforce Builder". I have signed up for Dev org. However, I am not receiving the welcome email with verification link having tried 4 different email addresses

Hello @Shashank Gupta,  Make sure you used this link : https://trailhead.salesforce.com/promo/orgs/build-a-service-agent

Make sure you have filled in a unique username. Check your spam folder then. 

Sometimes that takes time. In this case wait for a couple of hours before trying again. 

Eric