What should i master if i were to plan to major in automotive engineering?

Advanced math including Calculus AB, BC, 3 dimensional calculus and statistics.
Physics including kinematics, thermodynamics, statics.

Start researching what colleges you are interested in and look up their official website. Each one should have a "future students" or "prospective students" section where you can look up what courses are required for that major. Then research what those topics are about (through Wikipedia or any other source you trust) and you'll start to see common themes are what is needed to succeed in that area.

for example this for electrical engineering at University of Delaware where I went. http://www.ece.udel.edu/undergraduate/program.html
find your desired program and start researching on Google what each course title/subject means.

Engineering is all about math, science (in your case physics and thermodynamics) and logical and critical thinking.