How do I resize the contents inside an artboard when resizing the artboard automatically?

I do motion design in After Effects to animate and Illustrator to import designs into AE. I need to find out a faster way to resize artboards as well as the objects inside at the same time.

I receive Illustrator storyboards with a lower resolution than what I need in AE so everytime I need to save each artboard on its own and then individually adjust the resolution and resize the contents inside the artboard to fit the new artboard size but this just takes a long time and I can't find a faster way to do this.

So essentially I have two questions, how to resize content inside an artboard when resizing the artboard automatically and how to do this with multiple artboards at the same time?

Thanks!