How is prop firm trading technically different from live capital?

For example let’s say youre trading with $2,000 and your risk is 2% per trade so $40. Now let’s say you want to take a $50k eval which is usually $2,000 drawdown. It’s not feasible to use 2% risk of $50,000 so do you just use 2% risk of the drawn down? Or do you just use way more risk like 10% of the drawn down and hope you do good?

I just started PF trading and failed an eval and I realized I just got crazy with sizing because the account is $50k right? No not really. Also when I did good it doesn’t feel like I really did anything because it’s fake. If I do bad I have enough margin to easily size up and it just ruined my psychology.

I’m thinking about just going back to small account live capital because the risk is the same anyways. And I was doing good