You can not. It is impossible for Heartgold and Soulsilver.
The starters of HeartGold will be the same as Pokemon Gold and Silver which were Chikorita (Grass), Cyndaquil (Fire) and Totodile (Water).
Trade with other people who have heart gold or soul silver.
The Availible Starters Are -Chikorita Grass Type Pokemon -Cyndaquill Fire Type Pokemon -Totodile Water Type Pokemon They Are All Availible In Pokemon HeartGold And, Pokemon SoulSilver
you can't you have to trade
you cant get to the sinnoh region in Pokemon hart gold or soul silver but you can get the starter Pokemon at slip co (i think its called) once you done all gyms and defeated red (the Pokemon with emerald version).
There is no sinnoh region in heartgold or soulsilver, it is only Johto and Kanto.
All those pokemon would need to be migrated to Heartgold/Soulsilver.
you can't go to sinnoh in Pokemon soul silver.
That would be Chikorita one of the starters at the beginning of the games gold, silver and crystal along with heartgold and soulsilver.
you start out in sinnoh -_- you start out in Johto... And no you cant go to sinnoh but you can get the Pokemon by playing sinnoh tunes ;D