How to insert Records in Database using C# language?

Question

I am just a begginer on C# so i need too much help. Now the problem is that i have designed a windows form in which there are many fields like first name, last name, address

Answer 1

sql = "insert into Main (Firt Name, Last Name) values(textbox2.Text,textbox3.Text)";

(Firt Name) is not a valid field. It should be FirstName or First_Name. It may be your problem.