why wont the move on drive after a 8 hour in parking position unless force it?

What is your question?

mostly in the morning when i want to go to work.that first journey of the day.i will need to put it on drive the accelerate so hard to get it to move and once i am in a tarred road the gear works perfectly and no trouble again until the car is parked for atlease 6 to 8 hours.it gives a roaring sound until am on tared road and the sound becomes normal again.the sound is as result of accelerating the car for proper movement.

What makes this problem better or worse?

when its parked for too long before driving

How long has your 2014 Toyota Sienna had this problem?

for a week now