B.Com

You can refer this article for all the details:
https://www.shiksha.com/courses-after-12th/commerce

Bachelor of Commerce (Honors) in international finance & accounting integrated with Associate of Chartered Certified Accountant (ACCA) UK programme aims to strengthen a global profession based on the application of consistent standards.

Your B.Com admission in based on your 12th marks and for applying at Symbiosis you need to fill their college online application form with is available on their website.

Eligibility criteria for B.Com:
Minimum 40% required in 12th. Aggregate of one language and three best elective subjects would be considered as best four subjects (BFS). Environmental Education (ISC), Fine Arts, Graphic Design, Painting, Dance, Music, Physical Education, Home Science, Engineering Dr

Either go for courses related to stock markets, or go for marketing because mostly corporates now prefer more marketing skills from students side and stock markets are also having very well scope until the person is having good knowledge for the same.
All the best.

Yes, you are eligible for B.Ed if not with best university but with the good one whose cut-off for B.Ed is atleast low.

It totally depends on the colleges, that what kind of pattern they follow. Some of the colleges follow the semester system and some yearly. But most of the colleges conduct 2 semester in a year. So, before taking admission in any of the college ask about the semester system. I hope it's clear to you