Friend borrowed motorcycle and was hit by another vehicle

A friend of mine who also rides borrowed my motorcycle. They made it one mile down the road before someone pulled out in front of them. Police on scene determined the other driver was at fault. My friend is currently in the hospital with non life threatening injuries. They do not have a current motorcycle endorsement. They do own their own motorcycle that has liability coverage.

My main questions:

Who's insurance do I file a claim with on my motorcycle?

When should I file this claim?

If my motorcycle is deemed a total loss, will the other drivers insurance pay it off?

Thank you all in advance for your responses!