First, pick one of the objects to have the shade auto smooth. You have 2 competing smooths. So you have 3 ways to go.
1. On the cube.001 right click and click shade auto smooth. On the cylinder right click on it and select shade smooth.
2. Leave the cube.001 as shade flat and then right click on cylinder and click shade smooth.
3. Leave the cube.001 as shade flat and then right click on cylinder and click shade auto smooth
You could also do shade smooth on both, but that would look horrible so I didn’t put that as an option.
