For every post  that is offered under the SSC CHSL exam the minimum eligibility is that the candidate must have completed 12th science with mathematics compulsory from a recognised board . So if you are doing engineering you have two option either complete it and then go for a job or drop it.

I would rather suggest to complete your engineering and then apply for exams related to engineering domains and leaving behind SSC CHSL.

Go for exams like GATE, ISRO, BARC, SSC JE, RRB etc

Thank you