Can We Become Demons After Death?

I have some questions,I’ve heard that those who follow the left hand path will become a demon after they died,is that true?
I don’t know what it’s called,demonic ascension,dark ascension or etc
I’m very interested in it and I would love to do it if it is possible.
I’ve also heard a lot of legends about sorcerers who did this and I think it’s very cool to live like a demon! They have a very long life which is sometimes about tens if thousands of years! And they are very powerful and they have a very amazing life! It’s so cool to be like that!

Will you please give me some information about this?and if it is not the information you’re going to share with me for free at least tell me what it is and is this possible or not