FreeSurfer-8.1.0 for Rocky Linux 8 requires 2 important dependencies
- qt5-qtx11extras.x86_64
- libXScrnSaver.x86_64
To Install Dependencies, just
# dnf install qt5-qtx11extras.x86_64
# dnf install libXScrnSaver.x86_64
Once these 2 dependencies are in, you can easily install the freesurfer-Rocky8-8.1.0-1.x86_64.rpm from https://surfer.nmr.mgh.harvard.edu/fswiki/rel7downloads