Did 1 attempt in jee mains enough for entering into NIT ?After Jan 30 results can we know we got seat in nit or not??

No it is not that.
After April session ( 2nd attempt) the finalization of ranks will be declared which will based on the highest of two exams.
After 30 Jan they may show your score but you can not say that weather you get NIT ( you want) in that such marks.
Because if you score 200 in Jan and 230 the n April than your 230 marks will be considered and same for all candidates and rank will vary accordingly.
So you can not know about what you will get on basis of only Jan marks
Any other query always welcome.
So good luck.

If you are asking that just after the attempt one will you be able to know whether you are getting an it or not then it is not possible because when you attempt JEE main January session then there will be JEE main application and after both the session over then only rank calculation will be made based on the normalised a scores of the different sections of the JEE main and then those who appeared for both the session of JEE main for them the best out of to normalise scores will be counted for the rank calculation and based on this scores rank will be calculated and after that JEE advanced will be held so after 3 weeks of JEE advanced the result of JEE advanced will be declared and after that the process of counselling will begin by joint seat allocation authority and there you need to fill the choices and as per your choices you will be allotted your college so I think you will get to know about the colleges you will be getting by 30th June probably.

hai

Jhansi pulpaparthi

Yeah sir for 1 attempt only if you clear the score which the NIT is required for sure you will get the NIT adn even if you clear the JEE mains you can write the Advance this also cleared you can get the IIT

after the 30th jan you will get the notification about the seat in NIT

if any further question feel free to ask

All the best