Hello aspirant,
One thing to remember while pursuing your career in engineering is that you can learn coding and become a software engineer or a developer irrespective of your branch of study. But, computer science and electronics students stand a little higher chance in getting good jobs in the software field. If you are so adamant about getting CSE, then you should look for another college where you can get CSE.
But since you said that you can't drop, you can continue with the materials and metallurgical course and study coding in parallel. Always during first year the subjects are same for all the branches and before getting to second year, you can try for any spot allotment or lateral entry to get ECE or CSE.
The best thing that I would suggest you is to learn coding through the numerous online tutorials and online courses available and earn certificates. Participate in hackathons and do internships. All these record will surely get you a job in the software field irrespective of your branch of study.
Hope this was helpful
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