We were behind on our mort. we made partial payment, it was returned to us. In state of FL, can our debt now be forgiven?

No? Now they will be starting foreclosure. They are not required to accept partial payments.

What would even give you a idea that a debt would be forgiven

A lender does not have to accept a partial payment. Where did you get this idea that this could get your debt forgiven. All it means is that they will pursue the foreclosure option.