How to connect your phone to Wi Fi?
Such questions need to ask the administrator of your desired WiFi network.
Just wrote "Error autentifikatsii" immediately
Well here everything is clear, even grammatical errors the meaning is not distorted - do you have problems with authentication. Contact your network administrator.
Changed the mac address did not help.
And why it should help?
The MAC address must be changed to one that is allowed in the network. Ask the network administrator to give your address to the allowed list.