Different Manner in Restaurant

I know a few things about eating culture in the USA. One of them is about manner in restaurants. In Korea, when we go to the restaurant, we can have a seat anywhere we want, and we call a server to order foods. However, in the USA, we have to wait for a server, and we should follow the server to have a seat. And then, we still wait for the server to order foods. I heard that it's not a good manner to call a server anytime we want. Moreover, the most different thing is the tip culture. Their income is not good in the USA, so they need some tips. They might be nice to customers because of tips. They have their tables and they take care of everything for their tables. In Korea, usually, they don't have their tables, and they share the tables to take care of. There are no tips in Korea, but their income is not bad.