Diploma

If you are jobless and have plenty of money, you can do B tech from any University. That too, in the second year!
However, you are on the job, the only option is doing AMIE which is recognised.
See following links:
1. About AMIE [http://www.amiestudycircle.com/about-amie.html]
2. AMIE recognition [http://www.amiestudycircle.com/recognition-of-amie-exam.html]

No. You can't. You can do AMIE.
See the following link:
http://www.amiestudycircle.com/about-amie.html

Hi Shreyosi
If you have a keen interest in interior designing and have the required skills like creativity, imagination, innovation, eye for detail, you should definitely pursue a career in interior design. You can take up the course on your post graduation level. There are a lot of colleges that offer post graduate diploma and master in design in India. You can find the list of top 10 colleges here https://www.shiksha.com/articles/top-10-interior-design-schools-in-india-blogId-10599

Hi Biswajit,
In order to pursue graduation in Bachelor of journalism and mass communication, you need to have cleared your 10+2 from a recognised board of education with an aggregate of 50% marks. You will have to appear for an entrance test which is a general aptitude test. The entrance test has 4 major sections namely quantitative aptitude test, analytical aptitude test, English language test and general knowledge.