Hi vruti jivan,
It's great to hear you've chosen QuickBooks Online to help run your small business! I know how helpful it is to close the books on certain periods so that you know your transactions are protected from any changes. I'd be happy to explain how this works in QBO.
The first thing I'd like to note is that this is the Canadian QuickBooks Community. Since you've mentioned that you're using QuickBooks Advanced, you're likely using the American version of the program. If that's the case, I'd suggest posting your question on the US site here: US QuickBooks Community.
If you do happen to be using the Canadian version of QBO, you can follow these steps to close the books: Close your books to lock past transactions. At this time, there's no way to automate this feature to occur on a monthly basis. That's a great suggestion, and I'd encourage you to let our product development team know you'd like to see this included moving forward.
To submit feedback, click the Gear icon > Feedback.
I hope this helps get you on the right track.
Take care.
