I’m from two different countries so I have two cultures to talk about 
I’ll start with Indonesia first since I was born and raised there.
First, the currency. Our prices are in the thousands of Rupiahs. No, it’s not because they’re expensive, but our currency basically has a ton of zeroes.
To illustrate, the cheapest thing you can buy is some no-brand candy for Rp 1000. Sounds like a lot? Well it’s not because it’s just a single coin. We have coins in the hundreds of Rupiahs, like Rp 500 and Rp 200, but they’re worthless. Even poor people will curse you if you give them coins a pack of Indomie instant noodles is Rp 2000 here. No, it’s not expensive. It’s literally 14 cents (in USD). You Americans pay $2 for the exact same thing (which is why I brought back a ton of instant noodles to the US lol).
My mom has heard stories from taxi drivers here, when they pick up foreigners, they would always demand exact change to the hundreds of Rupiahs. Especially the white people. Meanwhile for us even if there’s Rp 2000 left as change we would just let the taxi driver have it because we know it’s not a lot.
So if you’re having dinner for five in a nice mall in Jakarta and you see the bill’s about Rp 1000000, don’t panic. That’s normal
The mosques’ speakers. Over here, mosques have loudspeakers. When it’s time for the Muslims to go to the mosque to pray, they would do azan (call the people to pray) using the loudspeakers. It’s loud. And it happens five times a day: at about 3 a.m., 12 noon, 3 p.m., 6 p.m., and about 8 p.m. if I remember correctly. I could be wrong but I remember staying up for 21 hours in a day regularly and to the point that I even kept track of when the mosques would sound. And here’s the thing: if you live in an area with multiple mosques nearby, they don’t do it all at the exact same time, so one mosque might start the azan later (and hence end later) than the other.
I didn’t really feel it before the pandemic because we’d mostly be outside at school or in a mall, and mosques are usually in residential areas. However, during the pandemic, when we were at home 100% of the time, I could really hear how frequently they sounded.
That’s why I find other countries quiet in comparison
Eating with one hand. Some countries eat with both hands, and then you have countries like mine, where people eat with one hand: their right. There are also other countries that also eat with just the right hand, because it’s the “clean” hand. My dad’s from the Philippines and he says that he finds it “skillful” how Indonesians can eat with just one hand. Meanwhile I’m like “I just like keeping one hand clean so that I can pick other stuff up without having to wash my hands first” 
Speaking of hands, giving and receiving with the right hand. The left hand is considered rude, so when you give something (like money) you use your right hand, not your left.
I’m not sure how much of a culture shock this is, but bidets. No, we don’t have those fancy bidets that the Japanese have, but bidets to properly wash your private parts are super commonplace here. I know other countries have bidets but a lot of countries I’ve been to don’t have bidets, including where I am right now, so maybe this can be considered a culture shock
Oh I can’t believe I forgot this, but lesehan! Basically in some Indonesian restaurants, you don’t eat at a table with chairs. Instead the table would sometimes be in some sort of open hut structure, not sure how to describe it, with a low table and some flat cushions, and you’d sit cross-legged at the table and eat there. Not all restaurants have it, but just the big ones with outdoor seating. And yes, you take your shoes off before you sit.
And this may or may not be a culture shock, but maybe being in a country that’s 90% Muslim can be a culture shock in itself if you weren’t in one. You can really see the influence the religion has in my country but we’re not strict about it. In fact, you can say that we don’t really “care.” Even if it’s fasting month, in the big cities at least, there will still be restaurants open during the day. Eating while walking will earn you some glares but they won’t go after you or anything. You can even be Muslim and eat pork and eat during fasting month and people will just give you glances at most, but they won’t say anything. It’s like, we’re religious, but at the same time we don’t care if people aren’t, if that makes sense? Oh and you do see a lot of women here wearing hijab, but you also see a ton of people that don’t. And burqas are virtually nonexistent here.
As for the Philippines, my other culture, I can’t really say as much because I don’t live there even though I go back there every year. Hmmm. One thing that I did find a bit of a culture shock was free water in food courts. Back where I am, drinking water from a tap and free drinking water in general is just a concept. The only places in my country with free drinking water I can think of are the drinking fountains in the newest terminal of our capital city’s airport. Other than that, we just buy drinking water.
Another thing that I considered a culture shock when I got to the Philippines is the use of slippers inside the house. I personally prefer to go barefoot, but whenever I go back to my family in the Philippines, we always put on either shoes or slippers inside the house. No going barefoot. Maybe it’s not like that in other houses, but I’ve always found it weird why they don’t go barefoot there.
I’m trying to think of more. Uh, despedida? It’s like this you know when a relative’s coming home from a far away country, and before they go back, we’d hold a despedida dinner for them. A farewell dinner, I think.
That’s all I can think of. I may or may not be back with more don’t hesitate to ask me anything! 
