I see advice to make reservation directly on GWR site and show the Eurail QR code when checking in. When I go to the GWR site to book, I have to pay to complete it so how do I book without paying?
Answer
using eurail pass
Best answer by BrendanDB
I think you’re still searching in the ordinary timetable/ticket booking module of GWR.
You need to make an account, and afterwards, when logged in, you get into a personal space where you can select “bookings” and then make a seat/bike reservations.
Looks like this:

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