What the most useful parts of a language to know on a trip and why?

If you had to pick essential parts of a language to know for a trip, what would you pick?

I’m planning on going to Asia (Malaysia, Japan maybe). and I am a lover of Romantic languages but my Italian, Spanish and what little Portuguese I picked up from BJJ I doubt will help much there lol.

I’ve got quite some time, because I think it might end up being next year, but if you had to go to a country knowing very little, what “little” would you pick, and what resources would you use to help with the rest?

Thanks in advance!