Question

I am getting problem in connecting to wifi.I am being asked to use security key.I dont know it.

Answer 1

If your router is a telone router, do not reset it!  i am talking about the huawei and cell pipe.)  you might not be able to get online at all.  Instead i suggest an ethernet cable then log in to the router and find your key.
usually you can login using 192.168.0.1 or 192.168.1.1

alternatively if your router has wps use that instead

Answer 2

then get the wifi key again from somebody that does know it, or reset your wireless router back to default - just double check the wifi key isnt on the sticker on the bottom of the router already though)

Answer 3

l dont think it is his/her internet wireless router ;)