Most Challenging part of Moving to a Different Country

I have been thinking to possibly move to a different country for a few years and settle there.

What are some of the challenging things you encounter when you relocating to a different country?

Culture shock.

Being away from my family is my number one. Food would be number two. I think you can adapt to another culture but the emptiness of being away from your family and friends never goes away.

Language and cultural norms are probably the most common issues.