I blew a timing belt while I was driving on the highway 60 miles an hour when It went with a bang, is is quite likely I caused some internal motor damage to the valves and pistons? where can I get info on how to change the timing belt and how to retime it? would you be able to send me a pic of the motor and its parts as to where the belt is and such

Could also be EGR Valve or THROTTLE POSITION SENSOR or FUEL PRESSURE REGULATOR.

Did you see them replace the belt ???
Its a complicated process, and should have taken several hours to replace. Mechanics sometimes lie.
If it was replaced, it's possible the failure occured from lack of oil, metal fatigue, hydraulic lifters can break, valves can drop into engines, any number of things can go wrong.
Unless you pay to have someone open the engine back up, there's really no way to positively prove what happened.

The OD is a extra gear do you need it not really you can drive 150 miles if anything its the switch button that went out

have your dealer inspect it for leaks, with this kind of mileage your valve cover gaskets, oil pan sealer and seals start to develop leaks, also try to use a good quality oil because areation is worst with cheap oils,

Does your motor have a timing belt or chain? If it is a belt and it was mostly highway running you should be able to get quite a few mor miles out of it. As a rule of thumb, city driving, jackrabbit starts, lots of cold weather driving(bellow -20f) and towing belt should be changed at around 80,000 miles. If is light duty driving 100,000 miles. If it is a chain you might never need to change it.

It is most likely the speed sensor in the transmission.

bang bang bang is ok. bada bing bada bing is not. you've got the 3bang problem. 3 bangs means the transmission and output shaft is locked. It will act like the motor is locked but it isn't. The tail isn't wagging the dog. The transmission is locked and the motor won't start, because of the 3 bang problem.

60-80,000 miles is a great benchmark for ANY vehicle. nissan recomends 105,000 miles which seems a little excessive to me. be careful because this engine is listed as an interference motor and WILL cause internal engine damage if it was to break.

they set the timing WRONG and that is an interference motor so the valves hit the pistons

Check the U-joints at the transfer case.