what is the cut off for nlu sonipat? can i expect to get admission in it with all india rank of 6045 in clat?

Yes, you should try with this rank.

Hey.
The cut off for admission in any of the National Law Universities through CLAT in the previous year was a rank in the range of 1600 for the general category. Considering that your rank is 6045  you do not seem to have any chances for any NLU including NLU Sonepat as the cut off for it won't be around a range of your rank.
There are various Private Colleges that accept CLAT scores other than the National Law Universities. You might even have a chance for colleges under IPU, Delhi if you applied there.
Here is a list of a few of them.
Jindal Global Law School, Sonepat
Kirit P. Mehta School of Law, Mumbai
NIRMA UNIVERSITY, Ahmedabad
ICFAI Law School, HyderabadSchool of Law, GITAM University, Visakhapatnam
Alliance School of Law, Bangalore
IFIM Law College, Bangalore
LLOYD Law College,Greater Noida
Amity University, U.P.
Asian Law College, Noida
Manipal University, Jaipur

Hello
As per my knowledge there is no national law university in sonipat and also with a rank of 6045your chances are pretty tough of getting into any if the nlus though you can apply to colleges that accept clat score like upes, ipu, alliance university these private colleges.
I hope this helps you and if you have any more questions please drop a comment below.
Best of luck.