That is an option, part of a package on the higher end trim models. Yes, U have to push button to open door. What you are looking for is Passive Entry System, see URL:
Due to the multiple configurations available we need your VIN.Free ground shipping for 48 Continuous States. Only to lower 48 States
nismopar.com
ADDED: Beware: Your Key Fob can transmit a long distance. I can be in my kitchen, which is opposite the living room. LR to main door out to truck. Like more than 50 feet away, and hit key, and house door is closed. I also have a steel roof which dampens signals, and I can still open and remote start my truck. SO when U R in an area that U have to be concerned about PPL trying to steal signals covertly to steal stuff, maybe walking around with your keys in a Faraday bag and not remote starting and opening your truck from far away may not be a bad idea. Just IMHO.