What do you call a person from another nation?

If they come from Spain, you call them "Spanish".

If they come from France, you call them "French".

If they come from the USA, you call them "American".

If they come from the UK, you call them "British".

If they come from China, you call them Chinese.

If they come from Iran, you call them Iranian.

It depends on where they come from.

If they are living in your country after migrating, you call them immigrants.

Some people refer to them as "foreigners", which is politically incorrect in some countries.

Don't be racist by referring to them in a racist name or "alien". To call someone an "alien", therefore to "alienate" them, means "isolated, turned away and lack of sympathy", making it a racist remark.