Ayelen Robredo's questions

I upgraded Ubuntu and now I have a problem logging in that I don't know what is causing it. When it boots up it says this on the screen and then a gray screen comes up saying there was a problem and the system cannot be recovered. With a button that says close session when I click it, it enters but it doesn't let me do anything, just move the mouse cursor, until the purple lock screen is put on and there it lets me see the calendar and everything that appears on that screen and choose to turn off.

The Ubuntu to which it was updated is 18.04.5 Has something like this happened to someone? Any idea how to fix it? Thanks.

Hello, I am with my first steps in Rails creating an app for a VideoClub, I need to know if a movie is available or if it is already borrowed. In the Movie model there is an availability attribute which is a boolean. Would I have to create a method on the model to access that attribute and see if it's true and then use what I get from there in another method on the controller so I can display a list of available and borrowed ones?

It confuses me what goes in the model and what goes in the control.