A level computer science varied mark scheme answers

For context, I do AQA A level CS, the mark schemes for the same questions from different years (I got from an exampro). However, the mark schemes are varied so much, a lot of people recommend using mark schemes to revise definitions, but they vary so much. And like some answers for a question from one year, might not be accepted for another. So I'm not sure what/how to know which answers to use?

Hiya,
I did OSC A Level Computer Science a couple of years ago around covid time and so kind of get the confusion and frustration around mark schemes and ambiguous information.
I know I did a different exam board so things may be different for you, but my several of my friends did AQA CS so I know how it was structured and roughly what the topics and exams were like.
For me, what worked best when it came to revision was go over the content and then closer to the exam do as many past paper questions and practise examples as possible. Generally with definitions, as long as the key words are included, the overall phrase or sentence is likely to be different for each student. Just remember to be clear and concise. Definitely check the best mark schemes with your teachers if possible and ask them to recommend study techniques and resources as they are usually the most helpful.
Hope that helps