We have lived in Honduras C.A. since 08/08/1993 as Christian Missionaries, but never earned enough to file income taxes until our Stateside sabbatical in 2019, now what?

We did file for 2018 and got a return since we had arrived before Thankgiving 2018, but we traveled around during our 13 months Stateside, so we are not what to put down as our address, not to mention several other things.