Toggle off the automatic system update switch in configs.
It also explains how to stop the Play Store from auto-updating your apps.
How Do I Stop Automatic Updates?

Updating a phone.Diy13 / Getty Images
Specific steps may differ based on the operating system version you’re running.
If you’re on a Pixel,enable developer options, then skip down to Step 4.
On some older Androids, you want to tapSoftware updateinstead.

Scroll down and chooseOther security parameters.
You’ll see thesettings/gearicon on some phones.
Tap the toggle next toGalaxy system app update.

Automatic OS updates are now disabled, so you’ll need toinstall them manuallyin future.
For Pixels, go toSystem>Developer options.
Scroll down a little and tapAutomatic system updatesto toggle auto-updating off.

If you don’t see that option, go toAuto download & install>Do not allowinstead.
you might turn off auto updating for all your updates or just specific ones.
Stop All Automatic Updates
Open thePlay Store.

Tap your profile image at the top.
TapDon’t auto-update apps.
TapDoneorOKto disable automatic app installations.

Stop Automatic Updates for Specific Apps
Want to disable automatic updates for certain apps only?
Tap your profile image at the top of the Play Store.
SelectManage apps & machine.

Tap the app you wish to change auto-update prefs on.
Tap thethree dotsin the top right corner.
Why Should I Keep My Phone up to Date?

While it’s possible to disable automatic updates for your phone and apps, it’s not generally recommended.
Here’s a look at the pros and cons of using auto-updates.
Navigate toSettings>Update & Security>Windows Update.
SelectAdvanced Options, then, in thePause updatesdrop-down menu, choose a date.
Automatic updates will be disabled until this date.
To turn off automatic system updates on your Mac, go to theApplemenu and selectSystem Preferences>Software Update.
Uncheck the box next toAutomatically keep my Mac up to date.
SelectAdvancedto control more specific update options, such as installing app updates.