The Kanto Region - Gen I
Leading Expert: Professor Oak
Starters: Squirtle, Charmander, Bulbasaur
Pokemon ID No#: 1-151

The Johto Region - Gen II
Leading Expert: Professor Elm
Starters: Totodile, Cyndaquil, Chikorita
Pokemon ID No#: 152 - 251

The Hoenn Region - Gen III
Leading Expert: Professor Birch
Starters: Mudkip, Torchic, Treecko
Pokemon ID No#: 252-386

The Sinnoh Region - Gen IV
Leading Expert: Professor Rowan
Starters: Piplup, Chimchar, Turtwig
Pokemon ID No#: 387-493

The Unova Region - Gen V
Leading Expert: Professor Juniper
Starters: Oshawott, Tepig, Snivy
Pokemon ID No#: 494-649

The Kalos Region - Gen VI
Leading Expert: Professor Sycamore
Starters: Froakie, Fennekin, Chespin
Pokemon ID No#: 650-721

The Alola region - Gen VII
Leading expert: there is none
Starters: Rowlet, Litten, Popplio
Pokemon ID No#: 722 - 809

The Galar region - Gen VIII
Leading expert: Professor granny (forgive me, I cannot remember her name)
Starters: Scorbunny, Grookey, Sobble
Pokemon ID No# 810 - 890