What follows are the steps I took to build PCRaster on Fedora (34) from source. I chose to build from source because I didn't want to use the conda installer and I could not find a stand alone package.

The process below assumes that you have a working QGIS build environment since some of the PCRaster dependencies are provided by the QGIS dependency tree too.

git clone git@github.com:pcraster/pcraster.git
cd pcraster/
mkdir build
cd build/
sudo apt install boost-devel qt5-qtcharts-devel xerces-c-devel ncurses-devel
ccmake -GNinja ..
ninja
sudo ninja install

To produce a debug build, replace the ccmake command with:

ccmake -GNinja -DCMAKE_BUILD_TYPE=Debug ..

After doing that, start QGIS and install the PCRaster QGIS plugin.

Once installed, you should see a new PCRaster group in your processing panel: