Explain Declarative and Procedural styles. The technologies you are familiar with (or using) are using procedural or declarative style?

Declarative - You write code that specifies the desired end state

Procedural - You describe the steps to get to the desired end state

Declarative Tools - Terraform, Puppet, CloudFormation, Ansible

Procedural Tools - Chef

To better emphasize the difference, consider creating two virtual instances/servers. In declarative style, you would specify two servers and the tool will figure out how to reach that state. In procedural style, you need to specify the steps to reach the end state of two instances/servers - for example, create a loop and in each iteration of the loop create one instance (running the loop twice of course).