Is there a way to hide modules from the menu in the customer portal?

Yes you can, Follow these steps to hide modules from the menu: 

1. Click the User Menu on the top right corner of the screen.
2. Click the Settings button.
3. Select Customer Portal under Configuration.
4. Scroll down to the Portal Layout block.
5. Disable the checkbox for a module under Portal Menu to hide it from the customer portal.

You can drag and drop the module names to rearrange them.

To learn more about configuring the customer portal, click here.