You can use any computer internet browser and log into icloud.com/find without being asked for a two-factor verification code. Note the "/find."
Another method is to log into icloud.com (without the /find) and ignore the two-factor request that appears and click the Quick Access to Find My icon below the two-factor window,
From an iPhone, see the following from Locate a lost or stolen device - Apple Support
You can help a friend find their device if it's missing and has Find My [device] turned on:
- Open the Find My app.
- Choose the Me tab.
- Select Help a Friend.
- Have your friend sign in to iCloud with the Apple ID they're signed in with on their missing device.