Help with stored procedure and update table
If this is SQL Server procedure, leave out the parenthesis and commas:

Create Procedure sp_PersonEditor
  @BusinessEntityId int not null,
  @PersonType nchar(2) not null,
  @NameStyle bit not null,
  @Title nvarchar(8) null,
  @FirstName nvarchar (50) not null,
  @MiddleName nvarchar (50) null,
  @LastName nvarchar (50) not null, 
  @Suffix nvarchar (10) null,
  @ModifiedDate datetime not null
as
  update BusinessEntityId
  set Title = @Title, MiddleName = @MiddleName
  where BusinessEntityId = @BusinessEntityId
end


Also, I would not recommend naming procedures sp* since that's meant for system procedures and causes performance overhead. Fixed also the typos (Business vs Bussiness). You don't have variables New* so I removed that prefix too.