There are more possible reasons why laptop with Windows 10 is turning on by itself. To disable automatic turning on, you have to check:
Wake Timers settings
To disable wake timers go to Control Panel > System and Security > Power Options > Change plan settings > Change advanced power settings, then select your power plan, expand Sleep and Allow wake timers, choose disable for "On battery" and "Plugged in".
Tasks in Task Scheduler
To open the task scheduler application, search for task scheduler in bottom taskbar. For example you can check Task Scheduler Library > Microsoft > Windows > UpdateOrchestrator
Windows automatic updates
Settings > Update & Security > Windows Update
Windows automatic maintenance
Control Panel > System and Security > Security and Maintenance > Maintenance
Other automatic updates
For example HP support assistant, Dell command, Acer care center etc.
Some people recommend to disable Fast Startup feature in Control Panel > System and Security > Power Options > Choose what the power buttons do > Change settings that are currently unavailable, then uncheck the Turn on fast start-up (recommended)
Some BIOS systems allow to set automatic turning on of the computer in Power Settings.