Diploma

You can check Mumbai University for the same.

You can pursue 3 years Diploma/degree or 1 year PG Diploma/2 years PG degree course. Doing D.Arch./B.Arch. will lead you to a professional interior designer or an architect.

Yes, of course you can change your branch, but if you want to change your branch in another field, this is totally new for you. So, I suggest you to do your engineering in civil branch.

If you are planning to be a graduate mechanical engineering then you are advised to study PCM at 10+2 stage and appear for engineering entrance examinations. You can also join Diploma in mechanical engineering after 10th and then seek lateral entry admission in B.Tech mechanical engineering. IITs & NITs do not have lateral entry admissions provision therefore if you take Diploma route for mechanical engineering, you will miss options of doing mechanical engineering in best engineering colleges of India.

Hello Abdeali,
SVIT Is the best institute for civil engineering.