I'm not very hopeful in getting a cheap 3018 CNC to cut aluminum well, but...
I'm not concerned about how long making cuts takes, so that should help. On
YouTube, a few are successful, but many are disappointed. From the looks of
it, I can guess they have no idea what type of aluminum they are cutting on.
One can expect using a high-speed bit in buttery hardware store aluminum will
produce bad results. But they don't know that. They think they're just cutting
on metal.

Someone mentioned an idea that had occurred to me and sounds plausible. That
is, using a cheap CNC for marking drill holes (like a mechanized center
punch).

Also, seems there is confusion about cut smoothly. One pours water in the
cutting bit area. Others use oil. More sophisticated appears to be mounting a
blower nozzle on the motor to blow away the chips (instead of the cutting area
being full of a sludge of chips in water or oil). I suppose best might be
both, I think one guy has oil and air blowing on the cutting path, but that
probably won't happen here.