Tips for plowing rows at a young age in a big tractor?

I'm sure your dad will draw the first row or two before allowing you to drive alone. Once on the tractor keep the idle low, lean over to the left or right to make sure the front wheel is in line with the tire row made from the previous path. As you get more confidence, give it more throttle. When you get to the end, lift the hipper, turn around, get the front tire in line again, drop the hipper and start the process all over again. If you get pulled into a row, remember to lift the hipper, reverse, get back in line. If you have the time you may want to learn to attach the harrow to do a few rows. That's when you really need to go in a straight line. Keep your phone in your top pocket and turn on the vibrator, he may call you, and you better answer. Bring water to drink and a towel to cover the back of your neck from the sun, and to dry your hands.

Safety first, listen to your dad, go slow and carefully you will get faster with practice and as you gain confidence. You should get into 4-H and take their tractor safety course. You can also get Extension Service publications on tractor safety, plowing etc.

Do exactly as your dad says to do, we have no way to know what kind of equipment you have or how it marks the next rows.

Listen carefully to what your dad tells you and learn from him.