Passenger door does not open

Hello, I am Danny.

Sounds like the door handle linkage inside the door has failed/broke. You will have to take the door panel off to inspect, but first you will need someone with a lock-out kit/slim-jim to open the door to gain access. I have attached a tutorial showing what is involved to take the door panel off. Hope this helps and feel free to ask questions.Thanks for using 2CarPros.
Danny-

https://www.2carpros.com/articles/door-panel-removal

I have a problem with my passenger door closing. how can I go about fixing it myself?

Hello again.

Does it seem like the door isn't closing by fault of the door hinges , Or the door not latching-staying closed from the door latch? I've attached picture steps below on how to replace the door hinges on your car. Get back to us and let us know if this helps. Thanks again for using 2CarPros.

Danny-