CHIKORITA!
In Pokemon Heartgold and Soulsilver you can get a Johto starter from Professor Elm, a Hoenn starter from Steven, and a Kanto starter from Professor Oak
You can't
You start out in the Johto Reigon.
after you finish your hoen pokedex and boy it that hard you get to choose one of the three johto starters and that's it!
They are Torchic, Treeko, and Mudkip. Reasearch them in a pokedex for more info.
In Pokemon Emerald, when you complete the Hoenn Pokedex, Proffesor Birch gives you a Johto starter. In Pokemon HeartGold and SoulSilver, after defeating Red, Professor Oak will give you a Kanto Starter and Steven will give you a Hoenn Starter.
Johto
Quite frankly, it is impossible to receive your Kanto starter first. You start the game in NewBark Town, which is located in the Johto region. In Professor Elm's lab, you can only choose between three Johto starter Pokemon. You can get the Kanto starter Pokemon later in the game.
You can get a diploma! You can also get a johto starter: totodile chikorita or cyndaquil. Choose wiseley.
Johto and Kanto
Johto.
It depends on if you choose cyndaquil for your starter Pokemon in the johto region. If not your rivel (Heart) might have it.