How to provide permission to a Profile/User on an object's record

Firstly login with sandbox: test.salesforce.com (given Credentials)

Go to setup ----> Administration Setup -----> Manage users ----> Users

There are lots of Users

Click on the Test Aarohi User

OR

We can Open the Profile from another way.
Go to Setup ----> Input the Profile (under the Manage users)

Click on the Profile Internal: Employee

Click on the Edit Button

This Custom Object has no permission set for Internal: Employee Profile

We have provided the Read, Create, Edit and View All Access permisson to this abc Object
Then click on the Save Button. Now this object is Visible for Internal: Employee Profile

There are three way to provide the permission to the User:

View All / Modify All
Using Sharing Set
Owner Access

View All / Modify All

Go to Setup ----> Administration Setup ----> Manage users ----> Profiles ----> click on the Profiles
----> Display lots of Profile ----> Click on the Internal: Employee Profile

Click on the Edit Button

Then click on the Save Button

Using Sharing Set

Go to Setup ----> App setup ----> Customize ----> Customer Portal ----> customer Portal settings

Click on the Customer Portal Settings

We can click on the New Button for creating the sharing sets

Click on the Setup button

Click on the Update button

Click on the save button

Its display the Configure Access

Owner Access

Click on the Account Tab ----> click on the New Button