Open the Settings app on your phone
Tap Passwords & accounts, Accounts, or Users & accounts
Select Google
Tap the Gmail account you want to remove
Tap Remove account
Confirm the removal
If prompted, enter your phone PIN, pattern, or password
On iPhone, open Settings
Tap Mail, Contacts, Calendars, or Passwords & Accounts
Tap the Gmail account
Tap Delete Account
Confirm the action
If you only want to stop syncing, open the Gmail app
Tap your profile picture
Tap Manage accounts on this device
Turn off sync or remove the account
If the account is the only Google account on the phone, back up important data first
Sign out of Gmail in any browser if needed
Restart the phone after removing the account