Colleges in Ahmedabad

Chances are slim, as they don't have any provision for work experience.

No, you cannot.
Admission into Masters Courses in IIT solely depends on your JAM performance.
Your graduation grades don't play any such role there.

Your academic performance is definitely above the minimum cutoff specified by IIMs. Hence, you are definitely eligible for admission in IIMs. However, you will have to write CAT and do really really well in CAT. With this score, you would not get an advantage of being in top 10 percentile based on prior academic performance. Hence you will have to be in top 0.5% of all CAT applicants. If you manage to achieve that, you stand a decent chance to get into IIM. So, complete your graduation and prepare for CAT and score well in CAT 98 or 99%tile.

Hi,
Interested candidate can apply directly to the college.
https://www.shiksha.com/teaching-education/course/diploma-in-teaching-in-english-dte-symbiosis-centre-for-distance-learning-ahmedabad-c-g-road-182320

Fee structure is not available online, it would be great if you can directly contact the institute for exact details:
Contact : http://www.navkarinstitute.com/contact/

You may get a call but due to poor academics, it will be tough to convert the call. Prepare well for GD and PI.

To be frank, you need to have 99.5 + percentile and exceptional 10th, 12th and grad scores around CGPA 9+.