India

Check link for details :
https://www.shiksha.com/university/abhilashi-university-mandi-56079/courses

Hello Viraj
As you are in the first year I suggest you to maintain your percentage without any backlogs. It will be great if you get a minimum 60% with good internship. You will surely get good placement as all airlines need good engineers to take care of their aircrafts. Even we want our engineers to be very good because we have to fly that machine as a pilot.
All The Best.Be Best to Serve Best.

Some of the best colleges in Karnataka for mechanical engineering:
RVCE
PESIT
BMSCE
BIT
RAMAIAH INSTITUTE
MVIT
DAYANAND SAGAR
JSS ATE
MVJCE
SJBIT
CMRIT

Considering placement, both have got nearly equal placement options . However, while selecting any college, just go through the placement records for different branches. Considering scope wise, both have got wide scope. So both the branches are awesome. At last, I will suggest you to choose your interest.

You can do BCA but you have the basic knowledge of computer application. And best college in Punjab is CGC Landran College but if you want best placements then go to Christ University Karnataka Bangalore. I will not force you. I am also going there for BCA next year even I live in Punjab. Best of luck

IIT Mandi and NIT Hamirpur is the best

Architecture does not have placements, you have an internship in your last year, you may continue with the same firm or apply to some other firm. An architects career opportunities vary such as
Entrepreneurs
Architects (Junior/ Senior)
Furniture design
Photography
Construction& Community based volunteering
Infrastructure development
Graphic design
Set Design
Jewelry design
Advance research in Architecture
Faculty @ School of Architecture
History, Restoration and Preservation
Interior design
Product design
Landscape Design
Project/ Construction Management

Which college are you looking at in both these university's ? Both Universities are well known, but you need to choose the right college in these universities. here is a link for all approved architecture colleges across India - https://www.coa.gov.in/index1.php?lang=1&level=0&linkid=25&lid=26

Dear Aayush
You can do some diploma or degree courses from Australia and starting working there and get your PR . for more information about studying in Australia you can contact MS. Chetna S on https://shiksha.com or www.bassekraah.com with your queries.
All The Best