I am new to application express 4.2 and I dont have any programming experience to write program, but I need help with one problem.
I have created a ticketing system. In that ticket system, I have a forum where it has customerid and businessname. Based on customerid it should automatically input business name in the business row. I know it is possible with programming but not sure how to do it in apex with minimal programing.
Your question doesn't carry all the required information. I think, you mean that you have a "form" (not forum) that has customer ID and name. How do you select or input the customer ID?
What type of page item is that? In Apex 4.x, you can use dynamic actions to refresh/set a page item's value based on another.
Apex 4.2 comes with a "Packaged Application" called "Sample Dynamic Actions". You can explore the different examples in that application.