Nemo tank

Hi, I'm new here and are setting up a FOWLR tank for my daughter. We took her to the pet store for freshwater fish and all she wanted were Nemo and his dad!

What we have (our neighbor gifted us this for free)
36 gallon bow front aquarium
2 aqueon HOB filters
Heater
Thermometer on tank
Light

What I know we'll need:
Live sand
Live rock - found on Craigslist already started
A place to get RO water or distilled water
Instant ocean
Protein skimmer?
Better filtration?

We have begun watching videos and reading about the nitrogen cycle.
Any advice or materials are appreciated!