How long do it take salt water or water to freeze and which one freeze quicker?

It is NOT a case of 'longer' or 'quicker'.

Salt water freezes at a LOWER temperature than pure de-ionised (distilled) water.

The freezing point of

pure de-ionised (distilled) water. is 0 oC

salt water is ' -6 0C '.

How long or quick it takes to go from 0 oC to -6 oC is a matter of time and the ambient temperature.

NB There is a whole lot of physical chemistry devoted to the depression of freezing points Cryoscopic Constants.

Conversely there is a whole lot of physical chemistry devoted to the elevation of boiling points EbulliOScopic Constants.

pure water boils at 100 0C

salt water boils at 102 oC (depending on conc'n of salt).

The above temperatures refer only to water at standard temperature and pressure (STP).