How can i transfer resources from one stack to other?

You can import them into the new stack using `pulumi import`https://www.pulumi.com/docs/reference/cli/pulumi_import/ which means that that stack can continue managing the resources and then delete them from the state file with

pulumi state delete

https://www.pulumi.com/docs/reference/cli/pulumi_state_delete/ which means the original stack won't be able to manage them anymore and you can remove them from the code

is it like importing all resources one by one?

Not necessarily. You can pass in a JSON file to the import command that contains a list of the resources you want to import. The import link about has the schema for that JSON file. Deleting resources from a state is done individually

i have a stack with some buckets in A i used

pulumi stack export --file buckets.json

and tried in stack B pulumi import --file buckets.json

You don't use the stack export to then use

pulumi import

. You need to build a json file according to the spec here: https://www.pulumi.com/docs/reference/cli/pulumi_import/ and then use

pulumi import

That's hardly a spec... any example how to use it? pulumi import shows me no resources to import