Yes.
you trade eggs.
Yes,you can.
Take them to Four Island after beating the Elite 4. You leave your Pokemon with a Ditto in the daycare and they'll have an egg eventually.
Most likely, yes. Ditto can breed with almost any Pokemon.
Yes, there is a special option in the union room
you cant
keep it in your Pokemon party and walk around heaps. eggs hatch after you've done a certain amount of steps. it's a togepi!
Yes.
yes you can trade eegs in Pokemon platnium I've done it before.
all Pokemon can be traded (even eggs) to Leaf Green with out the nat. dex. with the nat dex. you can trade to emerald, ruby and Sapphire. but not to the older games like crystal and red
Just look for a Pokemon with flame body ability and then your eggs will hatch.
ALL POKEMON except legendaries and pre evolved forms.
You cannot get Legendary Pokémon Eggs in Pokémon LeafGreen due to Legendary Pokémon being incapable of breeding.
you can go to the Pokemon daycare, and leave a compatible male & female Pokemon with them. or, you can leave a ditto and any other Pokemon except a legendary. the only legendary that can breed is rotom
you trade eggs.
You can breed all Pokemon except: Legendaries, Babies and Eggs.
All except baby Pokemon and legendaries the exception being manaphy.