Welcome!
About the water weight, I wouldn't worry. The day-to-day changes in weight that you see is basically all water (even when your weight goes down). It's the overall trend that is what you want to look at for fat loss.
I think it's great that you have fitness goals - those are good to have because some days/weeks/months the scale is just persnickety and it's nice to have something else to focus on.
With your nutrition program (haven't heard of it, so not sure of the details), it is likely that it is like a lot of other diet programs and so the encouragement will be laid on thick and be fairly cliche. I think it goes with the territory.
That doesn't mean the program isn't good, though (but as I said, no idea what it is, so I can't comment).
Good luck with everything! And welcome, again!