Azure offers a free trial that includes $200 of credit to use on any Azure service for 30 days. You can use this credit to practice data cloud concepts. IBM also offers a free tier that you can see here https://www.crackshere.com/stellar-data-recovery-professional-crack/ which includes various cloud services, such as Watson Studio, Cloud Object Storage, and more. You can use these services to practice data cloud concepts.
I don't think it is available for free. You will need to get in touch with your Account executive
See more: https://help.salesforce.com/s/articleView?id=sf.c360_a_product_considerations.htm&type=5
Related: https://trailhead.salesforce.com/content/learn/modules/salesforce-genie-quick-look/get-to-know-salesforce-genie
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