I do not see .deb packages for 32/64. I'm certainly missing something...
Use the tar file and install in your home directory.
apt install binutils make gcc subversion vim libgtk2.0-dev libx11-dev (and maybe libqt5pas-dev)
Get the tar file, extract it to somewhere in your home dir, set a path to the bin parts, put src somewhere in parallel. Don't try and install as root. Will use a fpc.cfg as a hidden file in home dir, need to run fpcmkcfg to generate it.
maybe, and this from (dodgy) memory,
fpcmkcfg -d basepath=$HOME/FPC/3.2.0 > $HOME/.fpc.cfg
(Come on folks, time we had a best practice doc for this ....)
Davo