Head over to iCloud.com on a different device than the one you are going to turn Find My off of.

Sign in with your Apple ID. If you've forgotten your Apple ID, you can look it up on your mobile device or reset your password here

Once signed in, you can bypass the 2-factor prompt and click on "Find Device"

Click on the Find My icon

Click on the drop-down menu and choose the device you wish to disable "Find My" from. NOTE: The device must be off in order to remove it from "Find My".

Click "Remove from Account." This will disable "Find My" from that device. DO NOT erase the device.

Open the "Find My" app on your iPhone, iPad or Mac.

On your iPhone or iPad - swipe right and click the red trash icon to remove the device

On your Mac - right click and choose "Remove this device"

On your iPhone or iPad - open the Settings app. Tap on your Apple ID.

Tap on Find My.

Tap on "Find My iPhone/iPad" (depending on your device)

Toggle "Find My" off.

You will be prompted to sign in via your Apple ID for confirmation.

On your Mac - click the  menu

Choose System Preferences (or System Settings if you are on macOS 13 or later)

Click Apple ID, and then click iCloud.

macOS 12 or earlier - scroll down to "Find My Mac" and click the [Options] button

macOS 13 or later - Click "Find My Mac"

Click the Turn Off button

For Apple Watches, the only thing you can do it unpair your watch from your iPhone.

Click the Watch app on your iOS device.

Tap on "All Watches" on the upper left

Tap the (i) next to your particular watch

Tap the red Unpair Apple Watch

You will be prompted for your Apple ID for confirmation.