Hi and welcome to the forum. ACC's are loaded automatically by TOS. All you need to do is copy them to the root of the disk you boot your machine with. Once you're at the desktop or within Cubase, you can access them via the Desk menu.
Mega"SST" 12, MegaSTE, STE: Desktopper case, IDE interface, UltraSatan (8GB + 512Mb) + HXC floppy emulator. Plus some STE's/STFM's