how to setup a greeting message when start conversation.

[FehrHassan]

Please help me more because the tutorial uses commands and i didn't get the actual effect of the command. For example when i run this command curl -X POST -H "Content-Type: application/json" -d '{ "account_linking_url": "ACCOUN_LINKING_URL", "persistent_menu": { PERSISTENT_MENU_SETTINGS }, "target_audience": { TARGET_AUDIENCE_SETTINGS } }' "https://graph.facebook.com/v2.6/me/messenger_profile?access_token=PAGE_ACCESS_TOKEN"

i got this message {"result":"success"} but i didn't get the actual effect in my bot. So please help me, I am a beginner at building bots :D