In such cases you have to rely upon your interest and what you really want to do in your life.

Now the best way to learn which will be perfect you is you should go through the syllabus of ECE and CS both. You may not understand all the facts mentioned their but you will get a rough idea about the subjects you are going to read in your later years. And thus you will feel a sense of inclination in one of the two subjects.

Now to help you , I am listing the purposes of the field which may lead help you:

1. ECE focuses mainly on fields including:

• Satellite communication
• Solid-state devices
• Analogue transmission
• Digital and analogue communication
• Basic electronics
• Analog integrated circuits
• Microprocessors and microcontrollers
• Antennae and wave progression
• Microwave engineering, etc.

2. CSE focus on:

• Computer Architecture & Organization
• Cloud Computing
• Database Management Systems
• Operating Systems
• Compiler Design
• Computer Networks
• Design & Analysis of Algorithms
• Compiler Design
• Data Structures and Algorithm
• Software Testing

This are some of the subjects that are at the core of the subjects. Now as you have complete +2 then you can make a basic knowledge about this subject and if you feel the interest in any of them then just go for it with out any second thought.

I hope my answer helps you. All the very best for your future endeavors!

It's always suggested to choose computer science stream. With no comparison both the streams are good and have pros in their own fields. But when compared , job opportunities, pay scale, job reputation computer science (CS) is suggested.
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Cs is all about coding and ECE is all about electrical work. Cs students program while ECE students work on it. Go for CS you and give your best in it. You will have a bright future