This is far beyond retarded but I honestly don't know the answer.

How do I:
>Enter food places (like restaurant, bar, diner, food court, street food, food festivals, small cafe, coffee places, etc)
>Order the food
>Eat it with acceptable manner (just enough to not look like a caveman who got trapped in the futuristic city and don't know western table manner, eating with hand, or chopsticks, but also not to look like a snob)
>Pay the food
>Wash hands
>Go to the toilets
>And get out of that place?

Ordering food is one of the most challenging things for me. I don't know if:
>I should approach the counter to get the food, sit and expect a waiter will notice my presence and offer me the menu
>Have a greeter that will guide me to a table
>Self serve (I really don't know what to do)
Or
>Other (like in Japan, when you order food by pressing button on a futuristic touchable screen and god knows what to do after that).

Not to mention:
>Calling for waiters to get extra orders
>Behaving properly to not annoy the workers and other people who eat there
>How to not behave awkwardly when I walk approaching that place and got a lot workers smiling and greeting me?

I rarely go to a clean and well-designed places like malls and neat offices (filthy third-worlder here), therefore I feel awkward, anxious, and inferior to people in these kind of places. So far, I researched the place by checking on their websites, social medias, google street view, YouTube tutorials, blog reviews, walking past the place to see how these places work, and when I'm sure, I go there. This method sometimes work, even though mistakes were made, but this is not enough because sometimes there are no information available on the internet, and the only way is to go straight at the place and try not to get heart attack.

Thank you for your help guys, I apologize for the failed attempt at asking a question nicely so bad that I made an insanely annoying long thread.