SOA University - Siksha 'O' Anusandhan

You can appear for the entrance exam and do well in that, score well and you will definitely get admission in this college.

Yes, you can still apply for the form. All the best foe your exam and study for them.

It depends on the field you choose to go into. SOA gives scholarships to it's student based on their marks in 12th board exams. For different field it has a different amount as scholarships.

NITs are a brand in itself. The faculty members you get in NITs have a very good standard and also the exposure you'll get in NITs and IITs are a class apart. Even the fee is also very low.
Now coming to DTU, getting into DTU is tough due to reservation for Delhi candidate but this college also gives you enough exposure.

For admission, both marks and rank is required, because college changes on every rank.

Yes you can take admission but you cannot do two courses at the same time.