How are the values of value types found (by the program that is using them) if we don't have their memory address stored? E.g., what is the address in memory of the variable x = 10?

Answer 1

That is what the CLR does in the background. That's why C# is a managed language. Yo will have access to the memory locations only by marking the code as "unsafe".

Answer 2

C# knows the memory address, you don't need to know it. When C# stores an object, it knows the memory address to which it stored it to.