Can cement nails be removed once they're driven into a surface? What's the process for removal?

Cement nails, those stalwart fasteners designed for the toughest of surfaces, are renowned for their steadfast grip and durability. 
Assessing the Situation
Before diving into the removal process, take a moment to assess the circumstances. Determine why the nail needs removal and evaluate the surrounding area for any potential obstacles or hazards. This initial evaluation sets the stage for a smooth extraction process.
Gathering the Tools
For the task at hand, gather your arsenal of tools. A trusty claw hammer, a sturdy pry bar, or a pair of resilient pliers will serve as your primary instruments. Additionally, have a drill equipped with a masonry bit on standby, just in case the nail proves particularly stubborn.

Loosening the Nail
If the head of the nail protrudes, begin by delicately prying it up with the claw of your hammer. For nails nestled flush with the surface or slightly below, employ the leverage of a pry bar or the grip of pliers to coax it from its snug berth.
Applying Leverage
With a firm grip on your chosen tool, apply gentle yet resolute pressure to lift the nail from its moorings. To safeguard the surrounding surface, consider interposing a block of wood between the tool and the material.
Using a Drill (if Needed)
Should the Cement nail prove recalcitrant, don't despair; turn to your drill for assistance. Equip it with a masonry bit and carefully drill around the nail. This strategic drilling can loosen the grip of the nail on the material, facilitating its extraction.
Removing the Nail
With persistence and patience, continue the extraction process until the nail yields, emerging from its stony sanctuary. Exercise caution to prevent damage to the surrounding area and ensure your own safety throughout the endeavor.
Filling the Hole (Optional)
Upon triumphant removal of the nail, assess the resulting cavity. Depending on the situation, you may opt to fill the void with an appropriate filler or patching material, restoring the surface to its former glory.