First of all, good luck on your trip! I hope you have a lot of fun on it. As for advice, I know it's scary, but I'd say to do it. Sometimes I get scared to do certain things in public, even though I want to do it, so I get it. Then, I think about it logically: most likely, I won't remember them and they won't remember me even a few minutes later. Even if they do, they likely won't bump into me again. That mindset helps me a lot.
As other people have said, try your best to not stress over it too much, bravely put yourself out there and learning at least a few common phrases of the language will all help you quite a bit as well. Just be yourself. Try and focus on doing what makes you happy, since having fun would be nice.
You’re right, people have better thing to do in their life than focusing on some stranger they met in sea lol… And like you said I shouldn’t think about it too much and just try my best to have fun, thank you