Can I use my Iphone 5 unlocked with no Nano Sim at all?

I bought an Iphone 5 unlocked but currently I have no Nano Sim at all.
Could I use the Iphone or is it totally disabled?
Because I can only put the language, country and select a Wi-Fi signal. Then it says that it has no Nano sim.
Finally, I try with Itunes, but it says
"There's no SIM card installed in the iPhone you are attempting to activate."
"Please disconnect and insert a SIM card in the iPhone."
Is there any chance that I use the cellphone with no nano sim?
thank you for all the help

Added (1). I bought it in Apple, brand new, unlocked

Where did you buy the phone from?

If you bought it online / from some random person and NOT from an authorized reseller, it is probably locked. Unlocking a phone costs a lot of money and someone probably wanted to get rid of their phone.

If you bought it from an authorized reseller, you can return it.