According to guidelines of NTA,

You can submit only one application at a time with one challan number. Multiple applications using one challan number will be rejected. but if you want to sit for more than one subjects and you have that many number of challans then ofcouse you can seat for the exams.

Get the complete details about syllabus of UGC NET Exams here (https://www.anujjindal.in/ugc-net-apply-online-syllabus-selection-criteria/) .

Good Luck!!!

Greetings !!

No, It is not possible to write two subjects simultaneously in UGC NET. You can focus only any one subject. For applying for UGC NET, you need to have a masters degree in your subject.  Stay focused, prepare well for 2020 UGC NET. if any doubts, pls feel free to ask.

Wish You Good Luck !

Thank You !!