I am going to be working on a bit of C# code on my own but I want to make sure that I follow the most widely accepted naming conventions in case I want to bring on other dev
I too had doubts about this and then I decided check github codes of Microsoft. All most every source code I've looked at had underscore usage for private fields.
https://docs.microsoft.com/en-us/dotnet/standard/design-guidelines/ document does not seem to mention about this usage.