All- I am taking the trailhead challenge from salesforce for Data Security - Records Access. Here is the challenge

Configure appropriate organization-wide defaults
You’ve been asked to create a custom object for tracking projects. The Project custom object records should only be visible to the owner of the record and users above the owner on the role hierarchy. Create the Project custom object and then create an organization-wide default for the Project object to accommodate for this use case.The custom object must be named 'Project' with a resulting API name of 'Project__c'.

I have done as per what is needed. But I still get this error. Can someone help please?

Challenge not yet complete... here's what's wrong: 
An object with the API name Project__c does not exist

Hi Experts,
I am trying to solve this challenge but not able to solve because of salesfore license issue. Salesforce only allows 2 'Salesfoce' license for DE. Is there a way to solve this challenge? Please help.

Create a Profile and Permission Set to properly handle field access
The Marketing Coordinator and Account Manager both require access to view and update Account Records, but only the Account Manager should be able to see and edit certain fields. Specifically, only the Account Manager should be able to see and edit the Rating field. The Marketing Coordinator should not be able to see or edit the Rating field. Create one profile and one permission set with the appropriate field-level security to solve for this use case.The profile must be named 'Basic Account User' and result in an API name of 'Basic_Account_User'. It should use the 'Salesforce' user license type.
The permission set must be named ‘Account Rating’ and result in an API name of 'Account_Rating'.