В чем разница между I've never been jealous of someone's something I don't have и I have never been jealous of something from someone that I don’t have ?Пожалуйста, приведите примеры.

1 and 2 don't make sense.

We wouldn't say "someone's something". And you could not say "from someone that I don't have."

The simplest way to say this is:
"I've never been jealous of something someone else has."
"I've never been jealous of other people's things."
"I've never been jealous of other people's possessions."

Also, "jealous" is not technically the correct word here. "Jealous" means fear of being replaced by someone. You get jealous when a new person starts talking to your crush.

"Envious" is when you want something someone else has. You are envious of their car, or their job, etc." It's good to be neither :)

But it is so common for people to use "jealous" when they mean "envious", that nobody would ever notice or misunderstand your sentences.