CBSE 10th

You must have to clear CAT entrance exam with good percentile first.

No, onlyafter class 12th you can pursue this course and M.A. English is an post graduate course you would to do B.A. In English to do so prior to this.

Yes, you can get and you will definitely get the college.

Yes, of course, you can appear in UPSC civil services exam, the only condition is-:
Candidate must hold a Graduate Degree from a recognised University. UPSC Civil Services Exam Age Limit: Candidate must be a minimum of 21 years of age and must not be more than 32 years of age.
General Category
No matter you had compartment in 10th or 12th but make sure you clear your compartment and have graduate from any stream and your degree recognised by UGC
You are eligible for UPSC Exam or any other Government job
I hope this will help you.

No the marks of class 12th is considerable. 60% in the CAT exam.

When you are thinking of writing the IPMAT exam. Then class 10th score will matter. Otherwise, for CAT it is not considerable.

Yes, you can do an integrated B.Tech. After the 10th standard at the Mukesh Patel School of Technology Management and Engineering. At its Mumbai campus, this institute offers a 6-year B.Tech degree programme after the tenth grade. The streams in which an integrated course is offered are:
1. Mechanical Engineering
2. Data Science
3. Computer Engineering
4. Information Technology
To apply for this course, you need to have passed the 10th grade with 70% in the general Science stream. You can apply for admission on the official website of the School of Technology Management and Engineering.

For programme B.Sc. Agriculture the following category scholarships are available:
Scholarship on the basis of Percentage in Qualifying Exam (12th or Diploma)
Scholarship on the basis of LPUNEST
Scholarship on the basis of JEE (Main)/ NEET
Other Special Scholarships (on the basis of innovations, start-ups or entrepreneurship)
Financial Aid (Need Based, Financial Aid to Orphans, Financial Aid to Persons with Certain Disability). .

Visit your School/College. Write the application to principal for duplicate Certificate stating the valid reason. Get the application verified and forwarded to Divisional Office of Your respective School.