True or false? a force is required to keep an object moving in a given direction.

False. Newton's first law of motion - every body continues in a state of rest or uniform motion in a straight line unless acted on by a resultant external force - so if it's moving, it tends to keep moving. Maybe the example of an ice skater (low friction) helps here. A push of from a side wall, and off they would go. Rather serenely.
Usually, there's an "invisible" force such as air resistance for a car which muddles things up a little.

Gas will most likely  fill the container