There is numerous sources in raising Arowanas on this forum. Big one is the Arowana sub forum!
https://www.monsterfishkeepers.com/forums/forums/arowanas.110/
Simple tips? Get a big tank, over filter the water, stay away from live foods and flake/pellet train early, make sure the tank is covered really good, and water changes!
Here’s the way I like to pick baby Arowanas. Most lfs’s will bring in a group of babies. I ask them to bring out a flake of flake food. Toss it in the tank away from the group. The one that comes out and eats the flake comes home with me! Pretty much saves me the time knowing he will eat non live foods, and he’s usually the strongest and boss of the batch anyways.