mr.g
that depends on what moves you teach it! =)
Almost all legendary PokeMon's attack but not all legendary PokeMon.
Legendary Pokemon are there to catch, are they not? The legendaries are just another Pokemon(some may know moves that are unique though). They are not just for wimps.
You can't
You go to POKEMON And then you click pokemon box and then you click the pokemon and then you there will be a yellow box saying: Change Moves
when you are battling a Pokemon use transform and it will bvecome that Pokemon and know its moves and ability for this battle (Works On Legendary Pokemon Aswell)
Well that is up to you :P
No, just some. Most of the time, legendary Pokemon are the only ones with signature moves that you can't even find on HMs or TMs
because lalalalalalallalalalalalalalalalala and that is why .............. al lalallalalalalallalalalala sory!
Every 10 levels, same as pretty much any Legendary
That is impossible without hacking into the game, and I strongly suggest you do not. Legendary Pokemon have ridiculous high stats and will just lessen the fun of the game. The normal starters can be stronger than legendary Pokemon if you train them and give them good moves, so why have a legendary? Besides legendaries are really slow in levelling and you will most likely end up underleveled.
Entei, because he is a legendary Pokemon and he can learn much better moves but on the other hand Charizard because he can use fly