Why Iam unable to send photos to other persons through text message, and MMS is not there

iMessage does not need an MMS plan. However, iPhone to iPhone: requires internet (Either over WiFi or Cellular Service) as it is sent over internet protocol. Needs Activation on your device too.

If you do not have internet or the iMessage is deactivated then you would need an MMS plan to send Photos to iPhone and Android users.

You need MMS enabled by your Carrier for the SIM that you use and then enable it in your Settings. See the Pic below