Those who remain in the Lake of Fire will be immortal beings:  Fallen Angels, Demons, and Evil Spirits.

Those who will be dead and dissolved in the Lake of Fire are mortal beings:  Unsaved Humans, Anti-Christ, and False Prophet.  How long it takes for this to happen is up to God.  The more evil may take a bit longer to die or dissolve.  Most unsaved humans will be dead and gone quickly.

The smoke that goes up from the Lake of Fire is forever.

If you read the Enoch Book, it seems Angels are used to bursts of plasma.  They can survive in such an environment, but will not be able to ever leave it.