If you put a car that’s turned off in first without using the clutch, will you damage your Gears/Transmission? Not that I would ever do this on purpose but every once-and -awhile I make the mistake.

heh. I don't think it will damage much since you're at low rpm, your car will likely choke up and die. What you have to worry about is the car jumping forward and you hitting a wall or another car.

if the car is off then the gears are not spinning. no harm no worries, i wouldn't try it with the engine running though. unless you know how. i had a pickup once and the throwout bearing went out so i had to drive the it without a clutch i got pretty good at shifting without the pedal! it wasn't too friendly on the starter however because in order to get the truck to move i had to turn off the engine, place it into 1st and the start it again. needless to say i had to rebuild the starter soon after lol.