N is used to specify a unicode string.
Here’s a good discussion: Why do some SQL strings have an ‘N’ prefix?
In your example
N prefix is not required because ASCII characters (with value less than 128) map directly to unicode. However, if you wanted to insert a name that was not ASCII then the
N prefix would be required.
INSERT [dbo].[TableName] ([Sno], [Name], [EmployeeId], [ProjectId], [Experience]) VALUES (1, N'Wāhi', 'ESD157', 'FD080', 7)