Top Bolt on the wheel bearing hub?

Hello,

If you are unable to remove the top bolt it is likely seized on. It could be helpful if you can use an impact tool to remove it. You can also spray some penetrating oil in-between the bolt and the threads to help it come loose.
There is not really any special trick to loosen it.

Removing the hub on this vehicle also requires a hub puller. The puller will allow you to remove the bearing hub from the spindle.
Those pullers can be rented from your local auto parts store.

Here is a helpful guide:

https://www.2carpros.com/articles/bearing-hub-replacement

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.