Tap the Messenger app icon, which resembles a bolt of lightning on a speech bubble. If prompted, enter your phone number and Facebook password to log in before continuing. It's a stack of horizontal lines in the lower-left side of the screen (iPhone) or near the top-right side of the screen (Android). This option is in the top-right corner of the screen (iPhone) or in the lower-right side of the screen (Android). A menu will pop up. It's in the menu. Doing so will bring up a text field in which you can enter a phone number. Skip this step on Android. Tap the text field, then use the on-screen keyboard to type in a phone number. It's in the top-right corner of the window. Doing so searches Facebook for a person whose name matches the phone number. On Android, you'll just tap Add contact and skip the next step. Tap the Add option to send a friend request to the person whose phone number you entered. If they accept, you'll be able to chat with them in Facebook Messenger.  You can also send this person a message, but they'll have to accept the message invitation in order to view it. If the number you typed in doesn't match a Facebook profile, you can tap Invite to Messenger to send an app invitation to the person.
Facebook Messenger को खोलें: तीन लाइन वाले "People" टैब को दबाएँ: + Enter Phone Number फोन नंबर एंटर करें: Save किसी इंसान को एड करें: