In NIT Warangal, there are many programs which come under Mechanical Engineering department like Additive Manufacturing, Automobile Engineering, Machine Design etc as you have not mentioned which particular program you are asking for so it would be better if you could go through the below link -

Gate NIT Warangal

You can refer below books-

AERODYNAMICS

Fundamentals of Aerodynamics - John D. Anderson, Jr. Aerodynamics for Engineering Students - E.L. Houghton, P.W. Carpenter

OTHER REFERENCE BOOKS: Gas Dynamics - E. Rathakrishnan Modern Compressible flow - John D. Anderson, Jr.

FLIGHT MECHANICS (Performance, Stability & Control) Introduction to Flight - John

Here are the syllabus for GATE in Aero space engineering:

GATE Syllabus for Aerospace Engineering 2018

Section 1- Engineering Mathematics

Core Topics

• Linear Algebra

• Calculus

• Differential Equations

Special Topics

• Fourier Series

• Laplace Transform

• Numerical methods for linear and nonlinear algebraic equations

• Numerical integration and differentiation

Section 2- Flight Mechanics

Core

Yes, you can do the same and if you want to go for M.Tech through Gate so you can write the Gate exam in any specific branch but the eligibility criteria and the list of courses offered vary college to college. Some of the IITs which offer M.Tech in Aerospace

No, you are not eligible for GATE 2018 as it requires 4 years graduation course like B.E/B.Tech/ B.Sc etc. Also, you can check the complete Gate eligibility below -

Gate Eligibility 2018

Or you can also try for below provided courses once you complete B.Sc Electronics -

MCA

M.Sc in

Some of the top colleges for engineering in Pune for Mtech are:

COEP
BVP
MIT, Pune
MIT College of Engineering, Pune
Pune Institute of computer technology, Pune

You can check the complete list here:

Top Engg Colleges in Pune

They take through GATE entrance.
Also you can check GATE cutoff