nobody with a manual will ever let you practice on their car
I’m sorry that happened to you. IMO folks are way more precious about their manual transmissions than they need to be. I’ve taught several people to drive stick – including myself, in a brand-new car I drove home from the dealer in rush-hour stop-and-go traffic – and it’s never hurt anything. (That brand-new car still had its original clutch when it was sadly totaled by a falling tree, 100k miles later.)