No, you do not need to learn exact statistics!! There is no need to remember percentages and no. of participants involved or in what they did. You literally only need to learn the key finding and then link this to how this has evidenced theories.
For example, say the question is regarding the social learning theory. You'd briefly explain what the social learning theory is. Then, you'd back this theory up using evidence which is the relevant study, stating the name of the study and possibly the psychologist if you remember their name (if not, do not worry as the actual study and theories is most important and can still allow you to achieve an A*). You would then explain very briefly the study's aim, and then its key findings. You would then conclude how this has led to our understanding of learning behaviour.
When it comes to revising, format your notes in the exam format:
Point - The social learning theory suggests that behaviour can be learnt through imitation.
Explain - This begins with observing a role model, learning their behaviour and then imitating the same behaviour. For example, children may learn to become aggressive through imitating adults who are their role models.
Evidence - Bandura's bobo doll experiment found that children observing the adult's aggressive behaviour towards the bobo doll led to the children displaying the same aggressive behaviour towards the bobo doll. It was also found that these children maintained their aggressive behaviour into childhood.
^ make sure you verify these points with your notes/handouts because I may have missed out some points or confused myself!
Hope this was helpful xo