Polytechnic

In government jobs, you have mostly scope in civil engineering, otherwise, mechanical or electrical engineering.

ID is possible after any +2 or +3.
ID is a lower qualification as compared to D.Arch.
You will get jobs under architects.
B.Arch/AMICE (Arch.) is the proper qualification.

Yes, BCA is a good option for Diploma in computer science, you can even opt for BCA through lateral entry (Direct second-year entry). For colleges, check out the link below:
https://www.shiksha.com/it-software/colleges/bca-colleges-india

Hello Sudhir,
Of course yes. You are eligible for lateral admission directly in 2nd year of engineering. But some states give admission based on marks of Diploma but some states give admission based on entrance test.

Hello Raushan,
Polytechnic is after 10th and BBA is after 12th. So, if you have started Diploma after 12th then only you have some chance of shifting to BBA. But, what is your passion? You are in the 1st semester of Diploma. Think, meditate, discuss with your parents/ teachers and then decide.

Hi Rakesh,
You must complete at least 12 year education to pursue Bachelors course. Your Diploma course must at least be of 2 year duration to qualify you for further studies. Your grades are very good, you are advised to contact some universities directly before you apply. Also, to study in USA, you must take SAT or ACT. International applicants must also take IELTS or TOEFL to meet the English language requirements. You will also have plenty of options in Australia. Good luck.

Not possible, as transfers aren't allowed in Maharashtra government polytechniques. However, you can seek fresh admission by foregoing the year you studied.

Hi Vedika, a student can mostly Polytechnic after class 10th, and as you are in class 12th, you should should go for travel tourism course. It has way better scope than polytechnic.