I am new to Salesforce and preparing for Admin Certification. Please help me with the below module where I am stuck up.

Define a Sharing Rule

1. In Setup, use the Quick Find box to find Sharing Settings. This is the same page used to define org-wide defaults.
2. In the Manage sharing settings for drop-down list, choose Job Application.  Choosing an object in this drop-down-list allows you to focus in on the org-wide defaults and sharing rules for a single object at a time rather than looking at all of them in a long page—a useful thing if you've got a large org with multiple custom objects. Let’s use this Sharing Rules related list to create a sharing rule that applies to both the Job Application and the Review objects.

I am not able to see any option called Job Application. Can anyone please help. I tried looking on the forum and community help and google. But did not find anything related to this topic. 

I am currently working on Beginner Developer Trailhead: Data Security: Define Sharing Rules - "Define a Public Group" section. I am stuctk at item no. 5 below. In the Available Members list, I DONT SEE SW Dev Manager, Director Product Management, or Director QA. Any direction is appreciated. Also, I don't see Recruiting Manger (item 7).

1. From Setup, enter Public Groups in the Quick Find box, then select Public Groups.
2. Click New.
The New Public Group page allows you to choose other public groups, individual roles, individual roles including the roles' subordinates, or individual users.
3. In the Label text box, enter Reviewers. Click in the Group Name text box to populate it automatically. Group Namerefers to the unique name used by the API and managed packages.
4. In the Search drop-down list, choose Roles.
5. In the Available Members list, select SW Dev Manager, Director Product Management, and Director QA, then clickAdd.
6. Go back up to the Search drop-down list, and this time choose Role and Subordinates.
7. In the Available Members list, select Recruiting Manager, and click Add.
8. Click Save.

Project custom object records should only be seen by the owner of the record and users above the owner on the role hierarchy. However, for some Project records, the Training Coordinator must also have Read Only visibility to the Project record.

Create a custom picklist field on the Project object called “Priority” with the following values: High, Medium, and Low. Then create a criteria-based Sharing Rule for Project records where the Priority = High to share those records with the Training Coordinator role.