Q: Not deleting iCloud

You should follow the steps in this article:

What to do before selling or giving away your iPhone, iPad, or iPod touch - Apple Support

It will not, as you erased all data.

It depends on what you did or didn't do.

If you still have the phone - then you can perform the actions recommended

If you do not and the person who has it - does not have the password to your Apple ID - they can restore the phone if needed and start using it

Turning off Find iPhone is key

That's OK.  The important thing to you is if the person you sell your phone to will be able to access any of YOUR data.  If you follow the steps in the article I sighted (even now) you can rest assured, he won't be able to.  BBoiss did answer the exact question you asked.