How long it takes to push baby on average?

I’ve been told by my doctor I will only have one hour to push and if I can’t deliver within that time then I’ll have to have a c section. This will be my first time giving birth. On average, how long does it take people. I’m really worried. I really don’t want a c section. I’ve seen my mom recover from both my sisters’ c section deliveries and it was so painful for her.

I just want a chance to deliver vaginally.