Newer verisons of Windows 10 are released approximately every 6 months, around April and September of each year, these will eventually download via Windows Update but if you want to upgrade manually sooner this video will show you how.
The Windows 10 Update Assistant downloads and installs feature updates on your device. Feature updates offer new functionality and help keep your systems secure. You’ll get these updates automatically after you download and run the Update Assistant.
If you don’t want to wait for an automatic update, or if you want to check for quality updates (which are more frequent and include small fixes and security updates), you can update Windows 10 yourself manually.
Windows 10 Update Assistant Download Page : https://www.microsoft.com/en-gb/software-download/windows10