It's fairly simple.
What phone are you currently using?
Either ways-
*if it's an older version
1. Go to Settings
2. Go to Sounds and Notifications.
3. All the way the bottom go to Lock Screen Notifications
4. There you'll see options to choose from
*if it's the newest update
1. Go to settings
2. Go to Lock Screen and Security
3. Go to Notifications
4. There are your optuons.