first most obvious, make sure the transfer case is not in neutral.
If the shifter is stuck in one position you can access the floor panel over the shifter, then remove the shifter, sometimes when worn or loose they can become stuck and you can fix it by lifting the shifter out of the trans.
Lastly, and you would probably already suspect this, the clutch is gone, but you would have had a lot of issues and slippage leading up to a complete failure.
The neutral safety switch keeps the starter from engaging when the transmission is in any gear EXCEPT park or neutral. A faulty switch would either allow the starter to engage any time or not allow the starter to engage at any time.
idler sensor!
Most likely a broken gear cluster
Bad transmission rebuilder
buy a Toyota
it's spelt 'litre'.
Check the fluid. If full, take it to the trans shop.
Gear oil...usually 75w90 weight. I would use Royal Purple or any synthetic gear oil. That goes for both differentials and the transfer case.
The tag on the back of the case has the part number, model number and gear ratio on it.
Stop the car, put it in 1st gear and dont change it, dont stop or put your clutch in for any reason.
You may need a new transmission, or you at least need to have that one rebuilt.
Snap ring is broken that holds the knob on. Turn the knob to see if it drops down. If this is not the problem it will be the mechanism in the handle.