Haha nice drawing. I don't know the species, but congrats!
I too recently just transferred my smaller community tank (CPDs, dwarf chain loaches, corys, guppies) into a larger one and found a sole surviving Celestial Pearl Danio fry!! (Yes all the adults are alive, just 1 fry). I always saw the fish spawning, but had no idea there was any fry. I am sure there have been a ton of eggs/fry, but they got eaten by the other fish. But still excited to know the fish were happy to breed.
For all fry, its rather the same, just feed tiny food (protein packed preferred). Baby brine shrimp eggs, hikari first bites, golden pearls, most powder fish food, etc. You can super finely crush the flakes. Some tiny live worms. Repashy gel food. Even a sponge filter that collected enough food on it is a good source food. You could even hard boil an egg (chicken egg) and crush up the yolk into a powder and toss a bit in for the fry to eat. A little goes a long way for such tiny bellies.