You can remove any device from your list of devices you've added to Dashlane. This process is called "revoking access." When you revoke access to a device, your data is removed from that device. The next time you log in to Dashlane on that device, you'll need to use an email verification code, 2FA token, or QR code in addition to your Master Password.
You can't remove the device you're currently using. You won't have the option to do so. If you want to remove the device you're using, you need to log in to Dashlane on another device.
For security and privacy reasons, Dashlane automatically removes devices that have been inactive for more than one year. If you want to use those devices again, log back in. You'll be asked to complete an extra step in addition to entering your Master Password, just like when you use Dashlane on a new device.