Without hacking, Kadabra cannot learn Hypnosis.
No, Kadabra does not learn Hypnosis in Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen or Diamond and Pearl at any level.
yes it can
you cant you have to find a Pokemon like hypno ,or a butterfree has sleep powder
Kadabra will learn it not sure when.
Snorlax does not learn hypnosis.
Kadabra and Alakazam both learn Psychic at level 40.
I think Gardevoir is a good Pokemon who learns Hypnosis at level 51
Kadabra learns Psybeam at level 24.
Drowzee and Hypno are top choices. but most psychic Pokemon know/can learn Hypnosis.
40
Munna and Sigilyph.
Jolteon can't learn Spark on Pokemon FireRed.