Hi Ann,
without any more details, I am afraid there is not a lot you can do.
BECKER is a common name in Germany, along with variations Bäcker, Baecker, Bekker, Baekker, etc, and Fritz (or more likely Friedrich) and Wilhelmina are also common names.
There is no equivalent website to the freeBMD or GRO birth indexes in Germany.
regards,
Bob