There's no Pokemon Black game online. It requires download as in ROM.
You can play the Pokemon games online for free on a Pokemon online simulator called shoddybattle. Or The Pokemon Moon Rpg
You can play Pokemon orange online below but you have to download it.
You cannot play it online.
you dont
Go to Pokemon indigo online.
Yes it is 100% free.
Yes, Pokémon White can play online with Pokémon Black 2.
Yes you can play free on line
with the code on the card
Pokemonindigo
playr.org, you can play pokemon games up to 2nd generation.