Dear student,

If you have given class 12th board exams from a particular state, then that will be your state of eligibility.

On official site of josaa, under the section of INSTRUCTIONS TO CANDIDATES (in the pdf) , it is clearly mentioned you have to submit - class XII marksheet / state of eligibility proof . That means you have to submit class 12th marksheet as your state of eligibility proof.

Also check out the following offical link to know which document to upload :-
https://josaa.nic.in/webinfo/File/GetFile?FileId=23&LangId=P

Also check out the following link to know More about josaa 2020 counselling :-
https://engineering.careers360.com/articles/josaa-counselling