Hi Sirjana,

I appreciate how clear you’ve been. Yes, you can still apply for Diploma in Mechanical Engineering after passing 10th  you don’t necessarily need to pass 12th for polytechnic diploma courses. Since you’re considering management quota, colleges may have some flexibility with deadlines. I'd recommend visiting nearby private polytechnic colleges directly or checking their websites  most colleges keep a management quota admission window open longer than government counseling

Thank you