Yes, you have to buy NoLimits 2 at http://www.nolimitscoaster2.com Or if you are asking how to run NL1 tracks in NL2, you just navigate to the NL1 file in NL2 and open it there, and NL2 will do the rest.
In the NL2 editor, open your usual park, or start a new one. Then choose the Coaster tab, and then click on Import. From here, you navigate to your NL1 coaster and import it.