I run a Data Engineering team at an insurance company.

Kimball's Data Warehouse has a few chapters that cover insurance data modeling. This is a good place to start for data modeling with insurance concepts.

There is also some underwriter's certification courses that you can take that give a good introduction to insurance. You can just study the material since you don't need to actually get the certifications. I'll try to find the actual certification I studied for.

Also, check out Lloyd's Data Dictionaries. You can get a list of commonly used policy and claims fields with their definitions. Lloyd's is for England but there isn't really a common standard/layout used in the US so this should be good enough starting point.

If your company has the license for it, definitely check Acord's data model. The license is expensive so I'd only get this if you are company already has access to it.