|Where do you want to access internet ? At home or at a public place ?|
If at home and you have security protocols enabled at the wireless modem / gateway side ( WEP, WPA, etc. ), then you have to define them to the machine you want to access internet from.
If wireless modem / gateway has other security options enabled such as MAC address filtering, etc., then you must find the MAC address of your wireless network adaptor of Medion laptop and put it into the accepted MAC address list of the wireless modem / gateway.
Wireless adaptor of the Medion laptop must be enabled in the Device Manager and the physical wireless switch ( if any ) must be in the on position.
After the above is all done, you can start with the internet connection wizard to establish a connection.
Hope the above helps.