How can I be a good computer science engineer being in my second year of engineering?
Well, you have not informed what TIER college you belong to, as, College Quality plays a vital role in determining your quality as an engineer at the time you finish your graduation. Anyways, let me try answer in generic.
Implement what you learn : There is hardly any concept in Computer Science curriculum which you cannot learn by implementing a demo or a prototype or writing a simulating application for the same. 90% of students mere do rote learning of concepts and vomit it out in semester exams. IT may fetch them decent grades, but the under the table knowledge remain obscure. This is a way to clear the exams, but not the way to gain knowledge.
Learn C/C++/Java : By the time you reach your 3 rd year, you should be able to write programs in all these languages, and expertise to a sufficient level in at-least one of them. I would recommend to go for C++ as it will cover your knowledge of Object oriented programming, as well programming at a low level as well.
Solve Data Structure and Algorithm problems : Data Structure is the first course you encounter the moment you step into your second year of engineering. It is the heart of Computer Science, and Algorithms which you will study in 3rd year is the soul of computer Science engineering. Starting from your 2nd year, be regular in solving problems based on DS and Algorithms for the rest of your life (or until you land in a job at-least). More you solve, better thinking ability to approach a solution will evolve over a time. Problem solving is something which strengthens over a period of a time. Solving hundreds of problems on the day before interview/exam would not meet the purpose. You can never excel 100% in solving a problem, there would always exists a problem which you cannot solve, you can only become stronger and better and more confident.
Excel in Core Subjects : Assuming, there are probably 5 subjects to study per semester, So, by the end of your graduation, you would have studied 40 subjects. please not that, it is vital that you grasp on core subjects of computer science : DS, Algorithms, Programming languages, Operating system/Networking, Automata. Rest of the subjects are complementary, and only some selective topics are required to be learnt by heart from them. When you have graduated, your computer science skill will be assayed based on the knowledge on these core subjects.
Become a self learner : Your teacher may not give you programming assignments on 90% of topics you learn. Become a self teacher. Think how will you implement the concept if you were to code it. Do it. Write a prototype or demo of the concept. Create your own Mini projects. For example, if you have just finished learning Data structures, say, Trees, create your own API with advanced functions on trees, such as, finding the diameter of trees etc. If you have just learnt the concept of Threading, implement producer Consumer problem. Don’t rely on your teacher to give assignments. Make your own assignments.
Follow Coding websites : There are 100s of programming websites on internet such as carrercup, codechef etc. Follow them at least from your 3 rd year of engineering and solve challenging problems. This will groom you over a period of time.
Disadvantage is not your college, but your Circle is : Make friends who are equally motivated to learn. Once you find yourself mobbed in a circle of such friends, learning becomes fun and easy. Once you tangle your self among peoples who only emphasize on completing the college curriculum, you will only end up in realizing that you stand nowhere in terms of knowledge and skills which your counterpart from IIT/NIT possess after 4 years of graduation. Circle is very important.
Don’t follow seniors advice, follow the advice of working IT professional : I have experienced, College seniors are the biggest source of misleading advice. listen to them, but evaluate their advice yourself. Follow Quora closely and see what peoples are saying. Securing Marks above the minimum threshold to appear for job interviews is not at all sufficient. College Brand does matter. Grades Does Matter. Securing job in a mass recruiter - say, Infosys, pulls you back by about 7–8 years as compared to your equivalent counter part from TIER-1 college who has managed to secure a job in core computer science MNC.
Chase Excellence, not the job : If you chase the excellence, it doesn’t matter what college you belong to, sooner or later you will share your shoulders with exceptionals in IT. Skills are values in IT. Being from TIER-n college you may not fetch interview call from facebook/Microsoft/Google in the beginning , but initially start your career with joining the startup or any xyz company. But, be sure, you do CS related work - coding. Then look for opportunities to grow. Your knowledge and skills will be the door to new opportunities, else, you will find yourself stuck in some low paying job for forever.
Follow what others are doing : Follow the websites such as sophomorehub(designed especially for TIER-n college students who need such advice), Coursera if you need advice or want to do online course, geeksforgeeks to practice problems, BJS facebook group to stay updated about what is going on in current market.