Trying to split objects in an .stl file

[torres]

Hello, I'm new to FreeCAD and 3D modelling in general. And my question might be dumb but I can't figure it out.
I need to print an stl file (not created by me), but it doesn't fit in my printer, and the file is two objects joined into one, so I wanted to split them and print them separately. I've done this before in Fusion360 but this is my first time with this program.
What I did was importing the stl file, then in the "Part" workbench selected "create a shape from mesh" and then tried to split them, but couldn't because it said it wasn't a solid object, tried to convert it to a solid object and it says that the "Shape is not a Shell".
I attached an image of what it looks like. Thanks in advance for any help or tips you can give me.

[TheMarkster]

Instead of converting in part, just use split by components in mesh design on the imported mesh object. Then export them separately from Mesh menu.