Hello and welcome to DC.
I assume you mean pans without a teflon (non-stick) coating.
If you are cooking a protein (meat, poultry, fish) in a metal pan, the fat pretty much doesn't matter.
Here's the key. Start with a clean pan and heat it to temperature then add the fat you choose to use and get that hot too.
Make sure the meat is dry on the surface and place it into the fat in the pan. Leave it alone for several minutes. Don't try to move it. It's stuck to the pan. After several minutes, a crust will form on the underside of the meat and it will release itself from the pan. Then you can turn it over and do the same on the second side.
The key is to add the dry protein to a clean hot pan with hot fat and to have PATIENCE so it can unstick itself.
"If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan