Apparently you’re learning that there are all kinds of cultures and all kinds of norms. Good for you.
Yes, in some cultures (and with some animals, too) it is considered disrespectful and “challenging” to look the other in the eye and not break contact (or even to look in the eyes at all), and in other cultures, such as most of North America, it is considered somehow rude, disrespectful or evasive to avoid looking another in the eyes at all. (It can also be “challenging” in the US, if it’s done in certain ways, as @jerv certainly knows.)
Most people will give you a pass on breaking their brand of taboo if they perceive that you do it out of ignorance or a misguided attempt to be polite in your own way. If they want you to be close, then they’ll tell you (or show you, if you’re attentive enough) when you are crossing lines with them.
There are a lot of taboos centered around feet, too. In some cultures showing the soles of the feet to another is the height of rudeness. Most Americans are familiar with the Iraqi man who threw his shoes at President Bush… and others who merely waved their shoes at American servicemen… both signs of disrespect. Then there are cultures where wearing shoes into a person’s home would be disrespectful, and others where taking one’s shoes off would be a faux pas.
It mostly helps if you pay attention and just try to get along.