Hi Yuzhu Li,
Thank you for reaching out to us on Microsoft Q&A forum.
In Unit 7 Exercise - Set up the product catalog, detailed steps have been provided.
Please refer to the screenshot provided for access to the Unit Group, where a link is available.
Upon clicking the link, you will be directed to a page where you can find the "Try for Free" option. Provided in the screenshot Please click on that.
Proceed by selecting "Dynamic 365 Sales" and then click on "Try for Free."
Provide mail address to proceed with practicing the exercise.
Once Providing mail ID. We can Practice the learn path exercise. Please find the reference screenshot.
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