That's not a normal rating for a resistor.
The resistor will be dissipating 96W, so it's a 1.5Ω 100W resistor.
To make one out of copper wire, you'd have to find some thin copper wire that is capable of carrying more than 8A and cutting a length long enough to have a resistance of 1.5 ohms.
If you looked at a table like
this, you could determine that you need 36.75 feet of 26 gauge wire. 26 gauge wire can carry about
20A, so that's reasonably safe.
However, you'll need to keep all that wire insulated, and it's not going to fit in a small space.
A neater option would be to get three resistors like
this, attach them to a heatsink and connect them in series.
For additional safety margin, I'd probably get 4 of
these and connect them in series/parallel.
You can get higher wattage resistors, but they're generally disproportionately expensive.