Check out example codes for "c# set a guid". It will help you in understanding the concepts better.
Code Example 1
// If you already have a string representation of the Guid, you can do this: Guid g = new Guid("11223344-5566-7788-99AA-BBCCDDEEFF00"); // And if you want a brand new Guid then just do Guid g = Guid.NewGuid();
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