Open the Google app, Gmail, or any Google service
Tap your profile picture in the top right
Select Manage your Google Account
Tap the account name or email
Choose Sign out or Remove account, if available
On a browser, go to Google.com
Click your profile picture in the top right
Click Sign out
If you are signed in on multiple devices, repeat the steps on each device
To sign out of all devices, change your Google Account password and review signed-in devices in your account security settings