37 degree 6'
The maximum degree of latitude, north or south, are both 90 degrees.
90 degrees north
The most northern latitude is 90 degrees north, at the north pole. The most southern latitude is 90 degrees south, at the south pole.
The northernmost latitude is 90 degrees north. Only one point is there ... the north pole.
The Northernmost boundary of India is disputed and so an exact answer is not possible. However, the latitude at 22 degrees North would pass through the halfway point along the North-South axis.
37 degree 6 minutes north
The equator is the longest line of latitude as it is located at the circumference of Earth, and the circumference of Earth is always the longest compared to anywhere as the theory is the same of the circumference of a sphere.
At 23.5 degrees north latitude, you would find the Tropic of Cancer. This line of latitude marks the northernmost point where the sun appears directly overhead at the summer solstice. It passes through countries such as Mexico, Egypt, Saudi Arabia, and India.
The international boundaries are not stable in the extreme north, in the region of the Karakoram moutains. My mapping software is about 5 years old. It shows the northernmost point of India at 35.49° north latitude, but a small adjacent area disputed with China that would extend to 35.96° north latitude. (That's a difference of about 32 miles in the north/south direction.) A popular website shows much more of this region as disputed, among Pakistan, India, and China.
The northernmost part of Texas is along the latitude 36.49°N - one city in that part is Booker, TX. The southernmost part of Texas is along 25.85°N where the Lower Rio Grande Vally National Wildlife Refuge is located.
The North Pole is the northernmost point on earth. However, the "northernmost" would depend on the definition of North Pole. The magnetic North Pole would be different from the Terrestrial North Pole.
The dividing line between North America and South America isthe international boundary between Panama and Colombia.The latitude of its southernmost point is roughly 7° 13' 30" north latitude.