So I can start feeding infusoria now or do I wait a certain amount of days?
When they hatched and starting to free swim, then yes.
For feeding infusoria the best way I found is to just put a load of plants like moss and floating plants in the tank from an established tank. There will be jnfusoria on this. Also can start feeding them bananaworms basically from day 1 of being free swimming. Bananaworms are a type of smaller microform. Microworms would work too. Then around day 3 I started feeding them live bbs but you can probably start even earlier. Try and get them on bbs ASAP! Good luck
You can also add leaves to the tank and as the leaves break down overtime, it will produce infusoria.