Please help

I came home to this today after a few hours from the grocery store. We adopted our Sonny a few days ago and have been practicing crate training. The crate is not what he has a problem with its separation anxiety. I do go to school for 6 hours 2times a week and we have a wedding we are attending coming up in 3 weeks. I don’t want him to hurt himself or get stuck in his crate. (He was okay after this incident in the picture. No injuries) he’s already a year old. Any advice on how we can help him overcome his anxiety quickly? (For note, he was raised outside only and has never been in a crate but was always leashed).