How do I get computer connected to a network I have a moden with wifi . I have tried everything I know I cannot connect to a network, What is an adapter Lorry86

I have a modem that has Wi Fi, I get Wi Fi connected but when I go back to computer it is not connected but I still do not have a network Lorry86

I have a problem with wireless connection cannot connect to a network and do no know where to find my network password lorry86