How to decide which university to go as an international(indian ) student

Avoid ULaw. It's not a state funded university, it's a private for profit company that also has been given degree issuing abilities. It's an office block in real life. Also since solicitors all used to have to do the LPC where ULaw was one of the few providers of it, they're aware of exactly what it is and what a law degree from there would be worth.
Of the options listed Cardiff is probably the strongest academically in general terms, although there may be specific specialist strengths the others have in your field that align better with your interests. Not sure how Cardiff compares to Bristol or Nottingham (I assume bigger than Colchester but who knows) in terms of offerings in the city. Of those options though Bristol is the most expensive city of the lot to live in so might be a factor.