Oops on walkthroughs

In my experience, as long as you have good teachers it’s better to do past papers yourself and ask your teacher to go through the question with you/explain if you get stuck - that way any questions or problems can be answered more specifically and you can get more personalised advice on how to improve, as well as better support on topics you find tricky.
However, if you find a youtuber who explains topics and answers in a way you find easy to understand (and has a good reputation for giving accurate explanations/information) - great, use those videos!

Are there any specific subjects you’re thinking of using past paper walkthroughs for?

Yes for science and csc

I think sciences would be good to use walkthroughs although I would definitely make sure to ask a teacher if you don’t understand a given explanation or if you think you were taught something different to what the video says. Not sure what csc is?

Definitely do some past papers without using the walkthroughs though just to get the exam practice in and work on solving problems by yourself.

What I find quite helpful when I get stuck (especially on longer maths questions) is looking at just the answer on the mark scheme and then trying to work the question back (sort of turning it into a ‘show that x = 1 using the given information’ type of question) so I know what I’m aiming to get but still practicing the skills and figuring out what I need to do to answer the q, then looking at the first step to give me a hint if I’m still stuck or think I’ve gone wrong.