Checking Login Status in FuelPHP

Nice to meet you.
We use FuelPHP to create a membership site.

FuelPHP has a controller. I can use the before() function, but I'd like to check the login status here. How do I write it?

Use the same URL for login and non-login.
You want to switch between views only.
Example: http://example.com/
(Login - > Member My Page, Non-Login - > Site Description Page)

I'm sorry that the language is not well organized, but I would appreciate it if you could teach me.