You should wait and ask your grandfather to teach you if you're that determined to learn. I'm sure he wouldn't mind at all. I know I wouldn't.
And no, if you've actually seen someone drive a stick before while sitting in the passenger seat...that's even better. It takes a little bit of coordination at first but once you get that worked out and out of the way...you're pretty much good to go. On leveled ground, it's fairly easy. Stopping at an incline and trying to shift from gear 1 to get the car going is a little tricky. If you don't know what you're doing you could end up rolling back and hit the car behind you.
Learn how to drive at a huge parking lot with little to no cars first until you understand the concept of driving a stick before taking it on the road. Smartest way to do it man.
FIRST
Its not a good idea. The reason being that when you "grind the gears" you are actually damaging the truck; and when you "ride the clutch" you are putting excessive wear on the clutch wear plates. So the bottom line is that I would be PISSED off if I were your grandfather and you did this behind my back.
SECOND
It is not hard to learn manual at all, provided you have a good teacher. When I was younger I taught several girlfriends and one girl friend and all but one learned no problem, with the other learning but not quite getting it right. The concept is super simple, you just need to learn how to properly feather out the clutch while feathering in the gas. Once you learn that, you are all set. But someone needs to say "too much" or "too little" while you do it and you need to not stall the car at speed or with anyone behind you, which can be dangerous.
Really not that hard, you just push the clutch when you want to change and you only change when your rpm goes off the chart.
Not relatively hard, as long as you have someone experienced in driving with a manual transmission.
not difficult at all.. supposing you are willing to be nice to the car and NOT grind the gears nor ride the clutch...
-Can't be THAT Hard... LOTs of People had Them; "Back in the Day..." ;)
I am a 20 year old guy and I have never had the opportunity to learn stick nobody has ever wanted to teach me.
My grandfather is out of town and will be gone for 3 more days so I am thinking about jut teaching myself on his truck since its just parked outside and he left the keys
good idea or bad idea of course I dont plan on going out into the street just within my neighborhood whihc is pretty empty during the day