I'm student of maharashtra, i am eligible to give other state exams like TNEA,KCET ,etc or not ?

No, if you dont have the domicile of Tamilnadu and Karnataka then you wont be able to get admission in Govt colleges but you can reserve seat in private colleges because residential proof is not mandatory for the same. Also, I would suggest you to give Jee, your state entrance, and private exams like BITSAT, VIT, SRM, Manipal etc and you can apply for other state's private colleges as per your interest and convenience. Note - There is no entrance test for Tamil Nadu as the admission are based on 12th merit only. Hope this helps!!!