Memorise these numbers:
1, 5, 7, 13, 28, 42, 46, 53.
Each number above is the first question of the next section of the Regs.
So, for instance, questions 1-4 will be on Part 1.
When you get to question 5, you will be on Part 2.
Question 7 (to 12), the answers will be in Part 3.
... and so on.
The City and Guilds specification for the 2382 Award (the 18th Edition exam) is at:
City & Guilds Requirements for Electrical Installations qualifications. Leading vocational education and training organisation.
www.cityandguilds.com
(go to "Level 3" then "Centre Documents", the current one is the PDF titled "
2382-22 L3 Award in Requirements for Electrical Installations 2022 handbook v1-0").
This document gives the specification for the number of questions on each section. Note that it does NOT state that the questions are asked in order of Parts. I took my 18th Edition exam within a week of the 18th Edition coming out, and within a day or so of the new City & Guilds exam going live. The questions were in a random order, and stayed that way for a few months... then they started putting them in order again. As far as I know (though I've been "out of the loop" as far as City & Guilds is concerned for a couple of years), they still ask the questions in order.
Note that you might have to go back and forward within a Part, it's not like you're guaranteed to aways be moving forward through the book.
The only caveat to the above, is if in the main bit of the Regs, there is to a reference to a specific Appendix, then the answer could be in there instead. For instance, question 10 (say), which you'd expext to be from Part 3, might ask a question about external influence code BA2 (or whatever), and you'll find the answer in Appendix 5, because this Appendix is referred to from Chapter 32.
The other useful tip I can give is that at the start of each Part - and, for Parts 4 and 5, at the start of each Chapter - there is a pretty comprehensive Table of Contents. So if you know (from the question number) that the answer is somewhere in Part 5, then the contents page at the start of Part 5 should help you narrow it down to a Chapter... you could then flick to that Chapter, and hopefully you'll be able to spot something that relates to the question being asked.