Hello,I have a question i want to Buy Intuit quick book software I have 10 to 15 clients, Is there is any option that I maintain 15 clients data separately?

One QBO account is for one company file. You should consider to use QB Desktop US version. You can buy a single license to manage multi company files. 

Welcome to the Community forum. I have here some insights to share about your query.

QuickBooks offers a wholesale subscription where you can manage multiple clients. However, it is unavailable on your end. It is only limited to selected regions.
 

As a workaround, I recommend having your client purchase their own QuickBooks Online (QBO) subscription and have them invite you as their accountant. This way, you'll have access to their data.

Moreover, if you want to switch to QBO Accountant, this article will help you get familiar with some of the main features and you'll also find links to other how-to articles so you can get your firm up and running: Get started with Global QuickBooks Online Accountant.

Feel free to leave a reply if you have additional QuickBooks-related queries. The Community team always has your back. Have a good one.