A homemade disk doesn't sound very good.
I'd use the original disks that came with the PC, both for Windows and for the drivers. Or maybe it came with a set of socalled 'recovery disks'. Or maybe you can still order those. Or maybe (but that wasn't a common thing when they still sold XP computers) there is a recovery partition to boot from that contains all you need.
All you can do: run a program like Belarc Advisor or Everest to see what hardware you have (it's usually done before a reformat, by the way). Then find the drivers from the manufacturers site. Or open the case and find what motherboard you have and what other cards (if there are other cards). Or maybe it's detailed on the invoice for the PC (it is with my custom built PC's). Or maybe it's a Dell PC you have. Then you just enter the service tag into their support site and it gives you all drivers you need.
The best thing to do is have your volunteer do all of this. After all, he made a mess of whatever he started with (might be another mess, but you don't tell why the OS needed reinstall).
If it's common hardware inside, you might find you can transform this machine in a fully working Linux (Ubuntu, Mint) machine (with video, audio and wired Internet). That's free. But that's only if nobody can fix XP for you.
Kees
I had my xp pro sp3 re-installed by a volunteer & his homemade disk. The computer is offline, there is no internet service. I have a chromebook & memory stick to copy driver files when found. This is coffeeshop access.
Device manager lists 4 problem devices:
1. nvidia network bus enumerator
2. pci simple communications controller
3. video controller
4. audio device on high definition audio bus
Follow each to properties & got the "name" for each. They are a long series of numbers_letters. Thinking this is the drivers, pen to paper, dress as its cold for july, get out my bike, go to "mcland" for coffee & internet.
Search: pciwen_10de&dev_0269&subsys_2a34103c&rev_a3\3&2411e6f&0&a0. I assume all the zeros are not o's.
NO results in google. Have not searched the other 3.
How do I find these drivers, get on to a memory stick, then into the offline computer?
Please do not respond in jargon, please do use the words found in windows xp as there is a search option for terms I do not understand.
Thank you for considering by difficulty.

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