Not sure how to remove your iCloud/ Google account on your device? Don't worry, you may follow the instructions in the links below to Remove all Apple/Google accounts

Apple devices:

Remove a device from Find My on iPhone

You can use the Find My app to remove a device from your Devices list or turn off the Activation Lock on a device you already sold or gave away. When you remove Activation Lock, someone else can activate the device and connect it to their Apple ID.

If you still have the device, you can turn off the Activation Lock and remove the device from your account by turning off the Find My [device] setting on the device.

Remove a device from your Devices list

If you’re not planning on using a device, you can remove it from your Devices list. The device must be offline in order for you to remove it.

The device appears in your Devices list the next time it comes online if it still has Activation Lock turned on (for an iPhone, iPad, iPod touch, Mac, or Apple Watch), or is paired with your iOS or iPadOS device (for AirPods or Beats headphones).

Do one of the following:
- For an iPhone, iPad, iPod touch, Mac, or Apple Watch: Turn off the device.
- For AirPods: Put AirPods in their case and close the lid or turn the AirPods off.
- For Beats headphones: Turn off the headphones.
In Find My, tap Devices at the bottom of the screen, then tap the name of the offline device.
Tap Remove This Device, then tap Remove.

Remove an iPhone Wallet with MagSafe

You can remove an iPhone Wallet with MagSafe and Find My support from your Devices list if you don’t want it to appear in the Find My app. Removing it from Find My allows someone else to connect it to their Apple ID.

In Find My, tap Devices at the bottom of the screen, then tap the name of your iPhone Wallet with MagSafe.
Tap Remove This Device, then follow the onscreen instructions.

Turn off Activation Lock on a device you have

Before you sell, give away, or trade in a device, you should remove Activation Lock so the device is no longer associated with your Apple ID.

See the Apple Support articles:

Turn off Activation Lock on a device you no longer have

If you sold or gave away your iPhone, iPad, iPod touch, Mac, or Apple Watch and you forgot to turn off Find My [device], you can still remove Activation Lock using the Find My app.

Tap Devices at the bottom of the screen, then tap the name of the device you want to remove.
Erase the device.

Because the device isn’t lost, don’t enter a phone number or message.

If the device is offline, the remote erase begins the next time it connects to a Wi-Fi or cellular network. You receive an email when the device is erased.
When the device is erased, tap Remove This Device, then tap Remove.

All your content is erased, the Activation Lock is turned off, and someone else can now activate the device.

** You can also remove a device online using iCloud.com. For instructions, see Remove a device from Find Devices on iCloud.com in the iCloud User Guide.

(Source: Apple.com)

Android devices

Add or remove an account on Android

To access your email, contacts, and calendar, and to get apps from the Google Play Store, you can add accounts to your phone. When you add a Google account, info associated with that account automatically syncs with your phone.

When you remove an account, everything associated with that account is also deleted from your phone. This includes email, contacts, and settings.

Important: Some of these steps work only on Android 9 and up. Learn how to check your Android version.

Add a Google or other account to your phone

Open your device's Settings app.
Tap Passwords & accounts. If you can't find "Accounts," tap Users & accounts.
Under "Accounts," tap Add account.
Tap the type of account you want to add.
- To add your Google Account, tap Google. When you sign in with a Google Account, the email, contacts, calendar events, and other data associated with that account automatically sync with your device.
- To add your Google Meet account, tap Meet. When you sign in with your Meet account, you can make and receive video calls, create meetings, and call devices linked to your Home.
- To add a different personal account, tap Exchange, Personal (IMAP), or Personal (POP3). You'd generally choose these if you use an email program like Microsoft Outlook or Apple Mail. Learn how to use IMAP or POP3 with Gmail.
Follow the on-screen instructions.
If you're adding accounts, you may need to enter your device's pattern, PIN, or password for security.

Tip: If you'd like to lend your device to a friend, you can or , instead of adding an account.

Remove a Google or other account from your phone

Open your device's Settings app.
Tap Passwords & accounts. If you can't find "Accounts," tap Users & accounts.
Under "Accounts," tap the account you want to remove Remove account.
To confirm, tap Remove account Remove account.
If this is the only Google Account on the device, you'll need to enter your device's pattern, PIN, or password for security.

(Source: support.google.com)