Don, make it snow and I'll drive up there and walk you though it.
If the wifi logo has a lock on it that means it's secured. You will need to ask for a password. Usually the small places will have it posted somewhere or they will give it to you if asked. There isn't a way you will be able to connected to a secured network without a password.
As @Deephaven mentioned, data is so low cost now that it doesn't save much money to not have cell data. I rarely connect to public wifi anymore unless there is no signal, which is common in your area.
Here is a good guide: https://clark.com/cell-phones/best-cell-phone-plans-deals/#cheapest