Trying to install build-essential:arm64 on pi4

To be installed on the pi4 itself or on my desktop/laptop (x86_64) ?

I tried installing on the pi4 itself, but the I’m getting
osmc@pi4:/opt/osmc-tc/aarch64-toolchain-osmc/usr/bin$ ./aarch64-linux-gnu-gcc-8 -v
-bash: ./aarch64-linux-gnu-gcc-8: Aucun fichier ou dossier de ce type

Suggesting it might not be meant to be installed on the pi4…