Is GCP account mandatory? e.g., can I use some other cloud provider, DO for example?
You may use any cloud, including DO, or local hypervisors like VirtualBox.
Hi Chris, do the labs build on top of each other ? in other words is lab 1 required to complete lab 2 or can I do lab 1 on VirtualBox and Lab 2 in AWS ?
Lab 1.1 exemplifies the creation process of a GCE VM instance because all the following exercises are assumed to be performed in the same environment. However, you can use an AWS EC2 instance, DigitalOcean Droplet, a VirtualBox VM, whatever technology you are comfortable with.
Except for a particular technology that is explored through many consecutive chapters, the exercises were not built on top of each other across chapters. Any such dependency between chapters is unintentional.