Hello @Wagner Luis Ferreira de Souza Thank you for your post!
Azure backup currently doesn't support to have different backup jobs for different folders. Suggest you to up-vote this feature here - https://feedback.azure.com/d365community/idea/7cde525b-0725-ec11-b6e6-000d3a4f0858 that would help product group to prioritize features per user demand for their up coming releases.
----------------------------------------------------------------------------------------------------------------------
If the response helped, do "Accept Answer" and up-vote it