Welcome Tmart. Sorry your first experience was a bad one. With all the basic questions....um, exactly what
have you researched? LOL No, you do not have to have fish. If you want to have a tank with nothing but plants no problem. Just me personally I would not add plants or anything living until after the cycle has completed, but that is just me. The rocks would be ok, but I might wait on the wood depending on what kind of wood it is. Even without fish you are still going to want a heater and a good light. Be sure to research your plants BEFORE purchasing in order to be sure that you will have enough light for that particular kind of plant. There are differing thoughts on the "window" question. Most believe that it is not a good thing, we have other members who are certainly NOT novices that will say they have had tanks (and still do) very near a window and have never had any issues. If you are really concerned about that there are two things you can do. First, pick another site so you do not have to worry about it or, be prepared if it becomes an issue to eliminate the source of light by installing light reducing blinds or curtains.
I hope this helps some and again, welcome.
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200 Amazon
Discus, Angel, Rummy Nose
Nano
2 Percula Clowns, 1 Chromis