How to give access custom module to individual users? I have a custom modules name "Employee Entry" and i want that module show only some of the users under a specific role. Like if i have a role office then i want there is few people who can access the content of that module. There is a by default option to give access to whole role but there is no option to give access for specific users.
The correct approach here would be to implement hook_permission to define permissions/a set of permissions to give your user roles specific access.

The Example module has some good info on how to use and validate permissions with hook_permission in your code. 

If you want to restrict certain users, the easiest approach is to create an additional role with those specific things and assign the desired users to that role.