Some of the original names which were changed were-

Hermione Puckle to Hermione Granger

Neville Puff to Neville Longbottom

Draco Spinks to Draco Malfoy

Lily Moon to Lily Evans

Madhari Patil to Parvati Patil

Mati Patil to Padma Patil

Harry only calls Draco ‘Draco’ twice in the series.

Lucius Malfoy wanted to send Draco to Durmstrang but Narcissa didn’t want Draco to be so far from home so she sent him to Hogwarts.