Well awesome job doing lots of research!!!
This article is a great resource to look back on and give you sound advice.
The main thing is to make sure to learn about the nitrification cycle.
And which fish you like the most and "build" your aquarium around them and their needs.
Some fish like high pH, some low, warm water, cool water, live in groups, live alone, etc.
Did you decide on which fish you want to keep yet?
Have a list of top favorites so far?
If not spend time going to fish stores noting what really interests you and catches your eye. And make notes of which fish you found and at which stores (in case you want to back for them later).
Some fish like fast moving clear water, and filtration needs would be different than fish which prefer slow moving "black" water. Mainly it relates to the environments which they come from in the wild, and how they feed, and live, even seasonally.
Are you the type of person who like the planning type phase of working on a project?
What sparked your interest in keeping an aquarium?
https://www.aquariumadvice.com/guide-to-starting-a-freshwater-aquarium/