Diploma

Those who are interested to make their career in maths and pure sciences can pursue B.Sc and later M.Sc, Ph.D.
Those who interested to make their career in engineering field, should go for B.Tech and later M.Tech followed by Ph.D (engineering).

Consider AMIE.
B.Sc elex. is not equivalent to B.Tech.
Pursue AMIE along with B.Sc elex.
Annamalai University offers the same B.Sc elex.

No, Diploma in EEE is not equivalent to graduation. Diploma students are eligible for direct second-year entry in courses like B.Tech, etc.

You need to appear for JEE Mains and Advanced examination, for more details check out the link below:
https://www.shiksha.com/b-tech/exams/jee-mains
https://www.shiksha.com/b-tech/exams/jee-advanced

Any Diploma programme has to be of at least one year's duration and a stock market is a vast field.
National Stock Exchange (NSE), as well as The Bombay Stock Exchange (BSE), offer various courses.
The NSE courses are broadly classified as
Certification on Equity Portfolio Management
Certified program

Top 10 Private Polytechnic Colleges UP for CS and electrical
1 Aeronautical Training Institute
Amausi Airport, Lucknow
2 D.E.I. Technical College Dayalbagh
Dayalbagh, Agra
3 Anar Devi Khandelwal Mahila Polytechnic
Vrindavan Road-Mathura
4 Balwant Rural Engineering Institute
Bichpuri, Agra
5 Central Footwe

Correspondence certificate has less value when compared to regular. Regular degree is given on attending regular classes and completing given tasks and on completion of the course certificate is awarded.
In correspondence degree, you just need to attend the exams and you need to prepare for the exams