My truck will drive in N

Sounds like you have a clutch issue. Your going to have to remove the tranny to inspect the pressure plate. Most likely its time for a clutch job. If its engaging in nuetral the the problem has to be clutch related. The clutch is the only link between the engine and trans.

Check the gear shifter lever.Also check the transmission. Also it indicates  linkage problem. The shift lever marker is showing you are in one gear when you are really in another. Check the other gears. Drive down the street with the marker in low see if it changes gears . i.e. it should not change. You can look at the tranny and find the linkage there should be marks on the linkage where the clamps have slipped.
 If it cuts off due to it bogging down then it is a transmission problem loading up the motor .Check the transmission.
Get the car scanned at www.autozone.com to get the error codes.
As per the error codes you can get the exact faulty part replaced.Its free to get car scanned at www.autozone.com service center.
Thanks.