NO one is automatically related, just by having the same last name. Consider the last name Lee.. which can belong to a White person in England, a Black person in the US, or a Chinese person in China. None will be related.
Is it POSSIBLE? Of course.. one scenario is that, unknown to you, your gr gr gr grandfather was from the UK, married in your country; and all his male descendants married women from East India. "He" may have had a brother who went to the US and had family. Or vice versa.. your ancestor was not from the UK, but his brother WENT there, had children, whose family wound up going to the US.
So.. the answer is "probably not" but "who knows, it is possible".. and you may want to research your ancestry. You would ALSO have to research their ancestry, and if you find a distant distant ancestor in common, then you will be distantly related.