The movie starts in an area that is now modern Iraq between the enemy Ottoman Empire and neutral Persia (modern Iran). The area doesn't border British India at all (which included modern Pakistan at the time and much closer to Egypt. That's about 800 to 1200 miles depending on the rout and start / end points.
The fighting at the start of the film takes place in a country bordering India. Then Cary Grant is transferred to a hospital in Egypt. Egypt is more than two thousand kilometers away.