As per your interest in Mathematics, you can opt for Maths and Computing branch in IITs or if you just like to solve problems that requires logical reasoning, finding out or customizing algorithms according to the needs of the user, etc., then you can go for Computer Science and Engineering or Information Technology branch in some good colleges.

Lol. All Engineering branches uses maths.
Maths is a very important tool buddy.
Since you have asked maths play a major role in computer science Engineering and electrical engineering.
Electrical Engineeringtends to use the most mathematics (Probability, Linear Algebra, Fourier Analysis, etc.)
Discrete math is sometimes referred to as the math for computer science. Topics in discrete math that are used in computer science include graphs, recursive formulas, counting, logic, probability and matrices.
So coose between CS and EEE. Which you like the most.