It would take a sympathetic race skipper to let a total novice work the chute. Too easy to destroy it, lose the race, lots of time to invest. Hopping a race boat as rail meat and observing how the chute is flown, sure. But...that's still just observing.
And the books, I don't know, I find it isn't the same as the hands-on and visceral feedback. I'd vote for taking any intermediate/advanced course that gives you actual time on a boat, with an instructor, who is going to have you working the chute for hours. And observing at other times.
I don't know UK courses, but this is common for any sailing school program.