In A Long Way Home, Saroo says “I’m obviously an outsider, a foreigner.” What does he mean by this?

The quotation comes from the Prologue to A Long Way Home. Saroo's just returned to the Indian village where he was born and raised, to search for his family. He stares in shock at the ramshackle old house where he spent the first few years of his life. Everything seems so different from how he'd always remembered it, not least the fact that the house appears so much smaller. Saroo has thought about this moment so many times over the years, imagining that, if he should ever return to the place of his birth, he would automatically be reunited with his loved ones. But his loved ones aren't there, and Saroo feels even more out of place than he already does.
For although this is the place where Saroo was born, he feels like a complete stranger, a foreigner no less. He's spent the last twenty-five years of his life living half a world away in Tasmania, which in cultural terms is about as far removed from rural India as you could get. Not only does he feel out of place, he looks out of place, too. With his modern clothes and hairstyle and his inability to speak more than a few words of Hindi, Saroo is almost like the archetypal Western tourist, even though this is the place where he was born and raised.