@Michał Pawlicki Thank you for your query!!!
Official and updated documentation for WVD is here and this is step by step guide to create wvd host pool.
You can refer to this article for detailed information on wvd and is a great source of learning too.
Moreover many users have reported this issue where When WVD was first released the documentation did not have the link to create the tenant, this caused a lot of confusion and led to that DSC failure on deployments.
You can refer to this GitHub thread as well for more info.
Hope it helps!!!
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