How to modify an addon?

[Zakuteiken]

I'm trying to modify a race but when i change something the race don't appear when i make a new character

[HousePet]

Would be better to make your own addon, rather than attempt to modify an existing one.
However using an existing addon as a base is a good idea.

[Zakuteiken]

https://postimg.org/image/se1dv3xhv/ i'm trying to change the image and the initial bonus, how can i make a new addon? sorry i'm new in this

[HousePet]

Start by making a copy of the folder/files.
Then you need to rename the folder and edit the init.lua file to contain your new addon name and other fields.