Prevent Windows 10 from Automatically Restarting Your PC After Updating
In the Settings app, go to Update & Security > Windows Update and then click the Advanced options button. In the drop-down box, switch the setting to "Notify to schedule restart."
AskVG notes that this won't disable or block Windows Update, but it will let you decide when to restart the computer. Their article also notes a "Defer upgrades" option that delays when updates are downloaded (except for security updates), but I don't have that option in my settings. If you want to delay
Head to AskVG for many other methods you can use to change Windows 10's update behavior.