Helo Hema.! Its good to see you that you are determined for gate from first year only. You can start preparation from second year as in first year you will read all the subjects including mechanics. The subjects will be from all the branches. But you can do one thing, just clear all the concepts, understand them( subjects of your branch i.e EE, math) . Solve aptitude questions as well.

Be determined and don't lose patience at all while preparing for gate exam. This exam needs determination,hope,patience and practice

Be calm and focused.

Thank-you