Hi, 

Hope you are doing well, both architecture and engineering are of different fields. But you will have to be perfect in maths in both the fields. Architecture requires maths without which you can't plan. If you choose architecture you will the other approach than Engineering but you have to master it to become successful. Engineering Mathematics is easy to understand and consists of complex numbers, Matrices, Differentiation and Integration and so on. Architecture is about design serving people in their daily lives combined with drawings and specifications.

If you are motivated by understanding people and how buildings serve them in their daily life and if you have an appreciation of beautiful architecture then probably architecture is the better choice for you. There is not much to tell about Engineering as it is the common course being taken by everyone these days in many streams like cse, ece, civil, mechanical, eee depending on their interest.

So, my answer to your question is both are best in their domains. It's you who need to choose according to your interest. There is still 2 months left for you to decide your career based on your own interest. Make up your mind and pick up wisely as it is going to lead you in the future. My advice is going with a different domain( Architecture) is better rather than being an ordinary engineer with no proper skills.  I hope I have clarified your query regarding B.Tech or architecture. Any other queries are always welcome at any time. 

I think it helps you!!!

Keep Smiling:)

*Chase your dream goal*

Wish you good luck!:)