Sometimes squeaky noises can be a result of a damaged belt. When you speed up, the noise goes away. You should get your car inspected by a mechanic.
gear ratio
it could be a bad universal joint.
A pebble.
when you take the car out of drive and put in park the drive mechanism or transmission does not put as much load on the engine so it runs faster.
Check your universal joints!
Check for a worn or loose drive belt.
The high pitched squeaking noise you are hearing is the warning device telling you your brake pads are worn out and need replacing. The grinding sound is the sound you hear when you ignore the squeaking noise and allow your brake pads to wear so much that the metal backing of the pad is rubbing against the rotor. Replace all brake pads on the same axle and have the rotors turned at a machine shop. You may end up having to replace the rotors if they are damaged too severely.
You could have a slipping clutch which is not transmitting the drive correctly.
Possible failed u-joint.
Drive belt too loose!
because of the alternator drive belt loosing
Check the tension on the belt; a loose belt will cause the battery voltage to go down because it may be slipping on the alternator and also squeals when you accelerate because the crankshaft is turning faster than the belt.