Hi,
Sandbox access is fairly new, and it's not something that is provided to all users... The current sandbox that I know about for the general populous is the one connected to the LinkedIn course.
I don't believe that you actually have to take the course to get access, the link to sign up for the sandbox is available to see in this section of the course: https://www.linkedin.com/learning/adobe-analytics-essential-training/accessing-your-adobe-analytics-...
This is the link if you don't want to check out the course itself:
https://adobe.ly/aademodata
You will need to fill out a form and wait for the access to be approved.
