hlwo Aspirant

hope you are doing well

I'll suggest you to go for PCM cause . For appearing in this exam you have to complete Degree from any stream but engineering is a good degree to pursue being an aspirant of IAS and you should also have 21 years of minimum age. To become IAS officer you have to give and qualify in Civil Service Exam.

The best branch will be CSE as it has many opportunities compared to others. You can do private jobs after graduating and prepare for UPSC at the same time.

if by chance you will not clear UPSC then atleast you have a good degree and you can work for industries

but I'll suggest you to do

BA hons would be a better option for you if you are targeting for UPSC. The subjects you'll study there will give you advantage as compared to Engineering because in Engineering the subjects are completely different from what is generally asked in UPSC.

IAS is a respectful and secure job. If you are concerned about payscale, then obviously an engineer can make more money than an ias. The sector also provides you opportunities to work in foreign. Good engineers get paid in crores. so if you don't clear UPSC then taking PCM will help you to do BTech and then after engineering degree you can also earn goods as well as you get opportunity to work in foreign

hope this is helpful for you

best of luck