Do you not have cellular service on the phone? Can you look at your old phone to see which network it's connecting to? Once you've determined that, you then need to get the password from someone with the permission to give such information. You can't just connect to ANY locked network, that's why they're locked.
How do you get your own network? Sign up for internet service, get the modem (and maybe the router) from the provider and use that network.
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