Just remove the battery and see the name of your cellular network on the SIM card that you have.
It could be Telenor(starting 034), Ufone(starting 033), Mobilink(starting 030), Warid(starting 032) or Zong (starting 031 I think). You can ring another number to check that.
For SMS to a number use Google and search "Telenor web sms" or "Ufone web sms" etc. Depending on the your cellular network.
For Email visit the network's website. Its different for every network.