How would I put my cell phone, a moto g(XT1028), on safe mode? it has the fbi virus.

The FBI "virus" is one of the most malicios malwares around, because it actually encrypts tour data files to blackmail you and they say, you may never get the decryption code, even if you pay.
Actually there are several version of this scam procedure and you should try to identify which one got in your computer, to neutralize and if possible, to get rid of it's effects.
Read some of these tutorials and may find more information doing a google search fror
Remove FBI virus..

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Load a good virus program such as malwarebytes or Avast and load on your computer and run to locate and remove the virus. You might have to use SAFE mode to get the program into your machine.

How can turn off narrator mode for Motorola smartphone XT1028 Verizon...

Mark
Motorola Support

Opposite of enabling it mentioned here. Unlock narrator mode for Motorola xt1028

Mark
Motorola Support

Thomas
Unlock narrator mode for Motorola xt1028

Mark
Motorola Support

Thomas

Unlock narrator mode for Motorola xt1028

Mark
Motorola Support

Settings > Accessibility > TalkBack > Enable

Mark
Motorola Support

Danielle

Many of our phones are now sold unlocked. If it isn't contact the current service provider. Some phones, based on their service provider cannot be unlocked.
Mark
Motorola Support

If you pull the battery and wait about 30 seconds, then put it back in you should be able to get to safe mode.

Boot up to avast rescue cd from cd/dvd device. Scan all drives and quarantine all suspecious files.