Laptop internet connection / storage

[Tink Tina]

Hi please help a very non techy person.

DD yesterday said she her laptop wouldn’t connect to the internet, checked and this message came up

Any ideas what this means and is it easily fixed?

We’ve got around the issue temporarily by connecting laptop to router via Ethernet cable but this isn’t ideal.

Also DD has all her college documents saved on the laptop and nowhere else. I realise this is risky but how should we store elsewhere, should I purchase a USB stick, would this be ok?

All help greatly received, thank you