A faux fireplace or a real one?
Here's a good tutorial: https://www.youtube.com/watch?v=oY38Sxkmels
If it's a real fireplace you need to make sure it's up to code
If you want a real wood burning fireplace you must have a permit to do this as it would call for a chimney.
Thank you for .
You can do gas logs and a small build out around them, similar to the electric fireplaces you can purchase. You can even put gas logs into one of those type units. That would be the smallest space.
Here’s how we built one! https://www.frugalfamilytimes.com/2019/05/how-to-build-faux-fireplace-in-corner.html?m=1
to try this