Ok so here's the breakdown;

I resurrected the hidden Darleen that's only visible in SimPE. I downloaded a clone of her from the Internet and i basically did the steps to resurrecting a Sim with no character Data (i went to the clones char file, extracted the files and placed them in a new folder and deleted unnecessary files and gave the files to Darleen. I also tried to swap the GUID numbers but i failed but hidden Darleen is now a fully playable sim with character data.)

Now that Hidden Darleen Dreamer is a functional Sim, her clone on the other hand has incomplete character data and is unplayable. Do i delete the clone or do i keep it? The tutorial never said anything about what to do to the clone once you've fully resurrected your sim. I am afraid if i delete the clone my Darleen will be corrupted.

Here's the tutorial i saw: https://sims.fandom.com/wiki/Game_g..._character_data

Well, the tutorial does not in fact tell you to delete any character data from the clone, so if you did that, you didn't follow the tutorial correctly. If you did follow the tutorial correctly, you can do whatever you like with the clone - delete it, or play it, or let it molder in the sim bin, it's up to you.

The clone's not in the Sim Bin. Clone's character data is incomplete and besides i unlinked her for no reason, but never dared to delete her.

Well yeah, if you unlink the clone it won't be playable in the normal way. If you don't follow the instructions correctly, you're going to wind up with something weird.

Always do stuff like this in a throw-away hood so there will never be a problem in your good hoods.
Or do it in a copy of your hood to be able to keep at least 1 good copy.

Yeah but it's too late. I resurrected the hidden Darleen Dreamer in my Main Pleasantview neighborhood. Nothing bad really happened, but the clone is useless and the tutorial never said what to do to the clone later.

If the clone is still there the best thing to do is place on a lot and use something to kill the sim.
That is if you can.