If you need to contact Nokia Care or your service provider, you may need info such as the model number and the serial number (IMEI). To see the info, tap Settings > about.
You can also find the info on your phone label, which is located under the SIM holder.
To open the SIM holder, push the SIM door key into the hole until the holder is released, and pull the holder out.
To see the phone label tray, put the SIM door key into the hole at the front end of the tray inside the SIM holder opening, and pull the tray out.