Level 2 is done in three, 2 hour sessions, so 6 hours in all on the road, for children and inexperienced adults.
I usually cover this in 1 or 2 sessions for adults and include some level 3.
A memory jog for those of you who have had training and a more complete explanation is here. Memory Jog Level 2
The High Way Code
Starting and stopping on road
Starting by a parked car
Road positions
How to pass a parked car or slower moving vehicle
How to pass a side road
How to turn left from a major road into a minor road
How to turn left from a minor road into a major road
How to turn right from a major road into a minor road
How to turn right from a minor road into a major road
This is the basic level 2 and nine year old children usually only do this, but with older children and adults we can go a little further and include some or all of the following.
How to negotiate a narrowing or country lane
How to use mini roundabouts
How to do u-turns