We had a house fire a few years ago and lost everything. Most of it was still intact, but it was ruined by smoke and water damage, so we had a contents inventory team come in and go through everything. They created an incredibly detailed inventory to give to the insurance company. If you would like for me to send that to you, just to give you a place to start with your list, I would be happy to. Please let me know if you need any advice about this -- it's incredibly difficult to lose everything, and if I can help ease your burden, I would be glad to.
We just had a fire in September, a very similar outcome. While it wasn't a total loss, a good deal of our belongings were lost due to smoke and water damage, so we have a very detailed inventory list for a lot of the rooms. I would be happy to PM you the list if you think that it would help.
Also, just mentally prepare yourself that the process may take awhile. That has by far been the hardest part for me- we are still fighting with the insurance company about repairs 9 months later and are not back in our house, and a lot of the delays have just been red-tape. It can be really frustrating. Take care of yourself.