I still don’t get actual “left” and “right” definition by Westerner.

The vast majority of Westerners don’t even really know what “left” or “right” mean. It’s going to be really confusing to rely on Westerners to self-identify their political beliefs, because every liberal seems to think they’re a leftist.

For example, people that support native people to be protected from encrouchment of their forest, as well as unmitigated immigration that will drive out them will considered both “left” and “right” side from Westerner.

It helps if we frame this in a context of imperialism and colonialism.

A refugee from Syria moving into Greece isn’t encroaching on anyone’s forests. That stands in stark contrast with a multinational corporation coming to DRC, clear cutting the forest, strip mining the mountains, poisoning the water, and paying pennies for labor.

Some Westerner also often assume their solution of problem is “the best” while all I can see is further division of society.

Absolutely. Any leftist in the West needs to spend their whole life unlearning their chauvinism.