Where are the field and constant naming rules for c#?

Types, Methods, Properties, Namespaces, and Enums have rules.

I see a field naming rule for Java, but not for C#. Also I dont see one for constants.

Are these missing for C# or am I searching incorrectly for them?

Hello @StingyJack
First of all thank you for reaching out to us.
Can you please specify a bit better what kind of rules are you looking for?
When speaking about Java, do you mean RSPEC-116 and RSPEC-115 ? By naming guideline for fields in C#, do you mean the Microsoft guideline?
You are correct, those rules are not implemented for C#.

I can specify some kind of naming convention for all of the other types but not fields and constants.

A selection from any of the usual ones would be fine
_underscoreCamelCase (preferred and the convention I see most often as it disambiguates between arguments and locals)

Fields and constants would not be held to the same rule, each would have its own. Like how the Java rules are done. Just because MSFT couldnt agree well enough to publish a guideline doesnt mean that other teams couldnt agree.