Develope software to find distance during site visit of its employee and paid travelling expences..

Start by looking at the data - you need three types of employee, each with its own food expense rate (criminal to my mind...), and two types of vehicle, each with its own per-kilometer rate. You could code these simple choices into listboxes, but since the rates may change you'll be happier with the result if you create a small table for each and use a lookup linked to each table in your data entry form.

You'll also need a table for trips, probably containing the traveler's name, employee type, vehicle type, starting odometer reading, and ending odometer reading. If you have a lot of travelers, consider making this a separate table so that you can look up the name (and possibly the employee class and vehicle type) using a listbox.

Create your database with these tables using Access, then create a Windows Forms application in Visual Studio. On the Data Sources menu, Add a Datasource and point the wizard to your Access database to add a connection to the database and import all the tables and fields to your project.

With these in place, you're ready to start coding. When you've made some progress post again with code samples and we can offer more specific guidance.

By the way, if this is a project to help you learn C#, it's a good one - hard enough to do some teaching, but simple enough not to be frustrating. But if you just need to bang something out for work that just gets the job done, you can easily do all that you require using Access alone and save yourself a lot of work. It's not a great database system, but for something this simple it's more than adequate.