The first amendment only protects non US citizens if they are inside the US, even when entering the US the protection is less strong.

When in the US it does not protect you from getting deported based on what you said.

Non American protestors inside the US have faced consequences for their actions, in the past.

To a degree that is perfectly sensible: You would not want foreigners to oppose you from inside.

https://cis.org/Fishman/Sorry-Mahmoud-Khalil-Aliens-Do-Not-H...

Still, first amendment is of less importance to us outside the country.