If the university is recognised by UGC then you can give the NET..The eligibilty criterion for NET is as follows :

• Candidate must have scored at least 55% aggregate marks (50% for SC/ST, OBC- NCL, PwD) in Master's Degree or equivalent examination from university recognized by UGC in Humanities (including languages) and Social Science, Computer Science and Applications, Electronic Science etc. to be eligible for UGC NET 2018.

For SLET also the mode of education does not matter..But it also have some eligibilty criterion that you should have passed standard XII exams or equivalent from recognised board with minimum 50 % marks ( 45% for SC/ST).

For Phd, you should have Masters degree in the revelant subject with atleast 55% marks ..for this you needto give a Research Eligibility Test..

Please feel free to ask if you need any further information..

Good Luck!!

National Eligibility Test (NET) and State Level Eligibility Test (SLET) have common eligibility that is,  you must be obtained 55% in master's for general and 50% for caste applicants from an recognised  UCG University or equivalent qualification. As for PhD examination you must have 60% or 6.75 CGPA in MTech/ME/MD and for MSc/MA/MBA/MBBS 60% or 6.75 CGPA with gate score equal to or higher than 300. As you have done your post graduation you just have a look for your eligibility according to marks and field here.