Hello @Richard2936
If by guest manual you mean the section where you can provide guests with a Guidebook that they can view when they click on your listing it's here:
In host mode:
==>Menu
==>Listing details
==>Info for guests
==>Before booking
==>Guidebooks and then EDIT
If it's where to put the house rules for your listing it's:
==>Info for guests
==>After booking
==>House Manual and EDIT
And if it's none of the above, just come back with a bit more info and I'll start again🤣
All the best
Joëlle
@Paula