I want to create a simple http service like web API in c#

I do not know what Taxas is. Do you mean Texas or taxes? Note that Texas is a state. Dallas is a city in Texas.

thanks for all the responses Let me clear the picture .

Unfortunately I need to modify my question a bit, Like I need to have one API which would work for saving as well as passing the flag or a bit value to another school like say 

DALLA: CAN ENROLL THE STUDENTS ONLY UPTO FIVE CLASS

TAXAS: CAN ENROLL THE STUDENT AFTER FIFTH CLASS LIKE 6,7,8

SO when some students comes to DALLAS the API need to check if it need to be enrolled less then five class then it wil enroll if not then it will return something so that the other side the TAXAS API consumer knows that its my student and they can enroll , how same api can be consumed at both school to achive this

Thanks Jayraj Chhaya for the response , my basic question was how two way communication can handle at the same time using web api like If I say the How this same API save the data at one use case and Pass the data to another school as second use case .

You need to create web api and u can refer from here (https://tinyurl.com/4d64rk9w) and dulicate functionality Web API and for duplicacy need to create SP and there u need to put logic and make sp parameters as per ur table definitions. No need to create 2 branches u can do it under one web api controller and a table. 

CREATE PROCEDURE [dbo].[branch]
      @username varchar(20),
      @pword nvarchar(20),
      @empname varchar(20),
      @email nvarchar(50),
      @designation varchar(20),
      @reportto varchar(20) AS
  IF (SELECT COUNT(*) FROM Users WHERE username= @username) < 1
    BEGIN   
      INSERT INTO branchUsers(username,pword,empname,email,designation,reportto)    
      VALUES(@username,@pword,@empname,@email,@designation,@reportto)
    END

To achieve the desired functionality, you can create a C# web API using the ASP.NET Core framework. Here's a step-by-step guide on how to implement the two-way enrollment process:

• Set up the API project: Create a new ASP.NET Core Web API project in Visual Studio or your preferred development environment.

• Define the data model: Create a Student class with properties like StudentId, Name, Branch, etc. This class will represent the student entity in your application.

public class Student
{
    public int StudentId { get; set; }
    public string Name { get; set; }
    public string Branch { get; set; }
}

• Implement the enrollment endpoint: Create an API endpoint that accepts a student's details and checks if the student ID already exists in the other branch. You can use a database or an in-memory collection to store the student data.

[HttpPost("enroll")]
public IActionResult EnrollStudent(Student student)
{
    // Check if the student ID exists in the other branch
    bool isDuplicate = CheckDuplicateEnrollment(student);

    if (isDuplicate)
    {
        return BadRequest("Student already enrolled in the other branch.");
    }

    // Save the student's details to the database or collection
    SaveStudent(student);

    return Ok("Student enrolled successfully.");
}

• Implement the duplicate enrollment check: In the CheckDuplicateEnrollment method, query the database or collection to check if the student ID already exists in the other branch.

private bool CheckDuplicateEnrollment(Student student)
{
    // Query the database or collection to check if the student ID exists in the other branch
    bool isDuplicate = // Your logic to check for duplicate enrollment

    return isDuplicate;
}

• Save the student's details: In the SaveStudent method, save the student's details to the database or collection.

private void SaveStudent(Student student)
{
    // Save the student's details to the database or collection
}

• Test the API: Use a tool like Postman to test the API by sending enrollment requests to both branches and verifying the responses.