I’m a bit confused about entry into the USA. I’m flying to Boston from the UK for a long weekend and meeting Canadian relatives there. We were then hoping to drive across to Canada and then I would Fly back to the UK from Toronto. I understand that you have to apply for ESTA and also the Canadian equivalent.
My question is: at US immigration would I satisfy the authorities that I have satisfactory travel arrangements to gain entry into the US? Also, would I be allowed to travel across the border by private transport? My flights have been booked.