You cannot find any TM Curse in Pokemon FireRed (Generation III) as it was a move in Generation II (Gold & Silver / Crystal).
It can be learnt by breeding. These Pokémon can learn 'curse' as an egg move:
Slowpoke
Slowbro
Slowking
Gastly
Haunter
Gengar
Torkoal
Shuppet
Banette
Duskull
Dusclops
Breeding in the Advance Generations is pretty much the same as breeding in Gold, Silver and Crystal, but there are a few changes. Here's how to breed in Ruby, Sapphire & Emerald, and FireRed & LeafGreen shared by Psypokes.com.
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