Pulumi stack init dev what does that do? If I tried to do this without any of the Pulumi.yaml, requirements.txt then I get error but if I do this inside the examples then nothing gets created?

Pulumi stack init dev what does that do?

https://www.pulumi.com/docs/reference/cli/pulumi_stack_init/

If I tried to do this without any of the Pulumi.yaml, requirements.txt then I get error

Yes - that makes sense.

but if I do this inside the examples then nothing gets created?

That does not sound right. A stack will have been created, but no resources will yet have been deployed until you do

pulumi up

.