Windows 10 will periodically check for updates and install them automatically by default, however it is sometimes desirable to manually check for new updates. For example, if you have not used your computer for a long time and would otherwise be far behind with security updates.

If you'd like to do this, please click on the Start Menu and select Settings:


Then click Update and Security:


You'll already be viewing the first Windows Update tab, so all you need to click on is the Check for Updates button:


If you haven't run the update for a while it may take a few minutes to complete.