I have checked the official page at the manufacturer's website and the laptop is listed as being compatible with Windows 7 and Windows 10. Although Windows 7 is just fine, I recommend Windows 10 because it's faster, newer and has better support for latest devices.
You can download the drivers using the following page: http://support.hp.com/in-en/drivers/selfservice/HP-15-Notebook-PC-series/8499326/model/8819356
Note: Make sure to select Windows 10 from the list then click on Update.
- Select proper Windows 10 and click on Update
- Expand the category.
- Select latest driver and download the package.
- Double click the installation package and follow the procedure.
- Do the same for the rest of the drivers.