Returning SoD Played on dead server and confused

Hey peeps,

Like the title suggests I'm a returning Player on an SoD Server which appears to be dead now. There is new stuff like of season of mastery (like a server that regularly resets?) and Classic era servers.

I'm confused.

Are there ways to transfer my charater to different servers? I would love to play on a "forever wow classic no expansion" server - does that exist?