It seems like you are encountering issues while installing portal packages from the Education Accelerator in Dynamics 365. Here are some suggestions and considerations:

Check Documentation:

Ensure that you are following the installation documentation provided by Microsoft for the Education Accelerator. The Puppe documentation often includes specific steps, prerequisites, and troubleshooting information.
Use Power Platform CLI:

The Power Platform CLI (Command Line Interface) can be a helpful tool for importing solutions. You can use commands like pac solution import to install solutions. Make sure you have the latest version of the Power Platform CLI installed.