how to fix the speedometer

I think it is cable driven so i would check the cable from the transmission to the speedometer that could be broken . Could also be the speedometer itself as well and the gear inside the cable drives or the gear that drives the cable from the transmission. If the cable is good at the transmission. Then I would remove the speedometer and send it to specialized speedometer shop for repair. If not cable driven and is electrical then it could be the cluster needing replacement if the speedometer can not be removed. Always disconnect the battery if it is electrical or not as it has lights in it as well . Make each wire if electrical and where it came from prior to removal. Take a photo or two wouldn't hurt .

Thank you. I found out that the needle is stuck behind the pin do you know how to get the dash cover off?

There are small screws to the left and right and also need to loosen the screws to the trim below the cluster panel as it will make it easier to remover the cluster trim. once removed it will need to be sent out for repair as this is very delicate work to remove the lens and repair the needle fault causing it to stick. You may have to remove the top cover of the steering column as well to remove the speedometer without scratching the top steering column cover. Remember to disconnect the battery positive.