big dent help

[killer_ssn]

hey guys
was a t sobeys today parked in the front waiting for my girl and a lady trying to put a cart away. well bitches cart hit my front fender (i think thats what it's called the panel that goes between the front tire and passenger door) and bounces back so i freek out and notice my passenger door won't open cause it's bent in. what is the best thing to do take it in or try and take off panel and push it out?

it's a 2000 civic sir black

roughly how much would it cost to fix?

thanks