Can't get wifi working

see if it works with a cable - prove the router is working OK

whats the make and Exact models of the routers ?

If they are also modems (ADSL ) then theres a chance they are setup for whoever gave them to you ISP login and that will need changing

Why have you got them ?
what are you connecting them to - A modem you have or another router
Who is your ISP broadband supplier ?

ADSL - means it has a modem and connects to a broadband enabled telephone line