i need access a text file & change individual fields

public static void UpdatePatientData()
        {
            string detail, choice;
     
            Console.WriteLine("Please enter the ID of the customer you would like to Update: ");
            ID = Console.ReadLine();

            string[] Name = File.ReadAllText("user.txt").Split('|'); // each field will represent an index from 1-4

            for (int i = 0; i < Name.Length; i++)
            {
                if (Name[i].Contains(ID))
                {
                    // here is where i would like to edit the name/gender/age etc and write it back to the file

                }
            }
        }