Look on the V5 if you are not sure, if it is an import then the details will not have been entered in full so..... there should be a plate on the bodywork indicating the size of the engine in c.c. on mine it was on the inner wing panel to the left when you look under the bonnet.
If you get the chassis number with all the letters etc you should be able to google it and find the model variant. The below websites should help. you.
https://en.wikipedia.org/wiki/Nissan_Pathfinder
https://www.vinnumberlocation.com/nissan-terrano.html
The VIN decoder on the second site shoud help.